SUMMARY

This summary highlights material information from this joint proxy statement/prospectus. It may not contain all of the information that is important to you with respect to the merger and the other matters being considered at the Silgan special meeting of stockholders and the Graham Packaging special meeting of stockholders. You should read carefully this entire joint proxy statement/prospectus, together with the Annexes, and the other documents to which this joint proxy statement/prospectus refers to understand fully the merger and the transactions contemplated by the merger agreement. See “Where You Can Find More Information” beginning on page 187. We have included page references in this summary directing you to a more complete description of those items.

Information About Silgan (page 148)

Silgan is a leading manufacturer of rigid packaging for consumer goods products. Silgan’s products are used for a wide variety of end markets and as of March 31, 2011, it operated 83 manufacturing plants in North America, Europe, Asia and South America. Silgan is a leading supplier of metal containers in North America and Europe, and is a leading worldwide manufacturer of metal, composite and plastic vacuum closures for food and beverage products. Silgan is also a leading manufacturer of plastic containers in North America for a variety of markets, including the personal care, health care, household and industrial chemical and food markets.

Silgan was incorporated in 1987 and is headquartered in Stamford, Connecticut, with its principal executive offices located at 4 Landmark Square, Stamford, Connecticut 06901 and its telephone number is (203) 975-7110. Silgan’s website is www.silganholdings.com. Silgan common stock is listed on the NASDAQ and trades under the symbol “SLGN.” Additional information about Silgan is included in documents incorporated by reference into this joint proxy statement/prospectus. See the section entitled “Where You Can Find More Information” beginning on page 187.

Information About Graham Packaging (page 150)

Graham Packaging is a leading U.S. supplier of rigid plastic containers for hot-fill juice and juice drinks, sports drinks, drinkable yogurt and smoothies, nutritional supplements, wide-mouth food, dressings, condiments and beers; the leading global supplier of plastic containers for yogurt drinks; a leading supplier of plastic containers for liquid fabric care products, dish care products and hard-surface cleaners; and the leading supplier in the U.S., Canada and Brazil of one-quart/liter plastic motor oil containers. As of March 31, 2011, Graham Packaging operated a network of 97 manufacturing facilities throughout North America, Europe, South America and Asia.

Graham Packaging is headquartered in York, Pennsylvania and was incorporated in 1997. Graham Packaging’s principal executive offices are located at 2401 Pleasant Valley Road, York, Pennsylvania 17402 and its telephone number is (717) 849-8500. Graham Packaging’s website is www.grahampackaging.com. Graham Packaging common stock is listed on the NYSE and trades under the symbol “GRM.” Additional information about Graham Packaging is included in documents incorporated by reference into this joint proxy statement/prospectus. See the section entitled “Where You Can Find More Information” beginning on page 187.

The Merger (page 43)

Upon the terms and subject to the conditions set forth in the merger agreement, and in accordance with Delaware law, at the effective time of the merger, Graham Packaging will merge with and into Silgan and the separate corporate existence of Graham Packaging will cease and Silgan will continue as the surviving corporation after the merger.

We encourage you to read the merger agreement, which governs the merger and is attached as Annex A to this joint proxy statement/prospectus, because it is the legal document that governs the merger.

Merger Consideration (page 86)

Silgan Stockholders. Each share of Silgan common stock outstanding immediately prior to the effective time of the merger will remain outstanding and will not be affected by the merger.

Graham Packaging Stockholders. Each share of Graham Packaging common stock outstanding immediately prior to the effective time (other than excluded shares) will be converted into the right to receive (a) 0.402 shares of Silgan common stock (which we refer to as the “exchange ratio”) and (b) $4.75 in cash, without interest (collectively, we refer to this as the “merger consideration”).

No fractional shares of Silgan common stock will be issued in the merger. Instead, holders of Graham Packaging common stock who would otherwise be entitled to receive a fraction of a share of Silgan common stock will receive, upon surrender for exchange of Graham Packaging common stock, an amount in cash (rounded to the nearest cent), without interest, equal to the product of such fraction multiplied by the per share closing price of Silgan common stock on the NASDAQ on the last trading day immediately prior to the closing date of the merger, less any applicable withholding taxes.

The exchange ratio is a fixed ratio. Therefore, the number of shares of Silgan common stock to be received by holders of Graham Packaging common stock as a result of the merger will not change between now and the time the merger is completed to reflect changes in the trading price of Silgan common stock.

Ownership of Silgan after the Merger. Upon completion of the merger, former Graham Packaging stockholders will own approximately 29% of Silgan’s outstanding common stock (based upon the fully diluted number of shares of Silgan and Graham Packaging common stock issued and outstanding as of April 12, 2011).

Graham Holdings Merger and Subsequent Transactions (page 106)

Immediately prior to the effective time of the merger of Graham Packaging with and into Silgan, Graham Holdings will merge with and into Graham Packaging, with Graham Packaging surviving the merger (which we refer to as the “Graham Holdings merger”), pursuant to a separate merger agreement entered into concurrently with the merger agreement governing the merger of Graham Packaging with and into Silgan. At the effective time of the Graham Holdings merger, each issued and outstanding partnership interest of Graham Holdings (other than partnership interests owned by Graham Packaging or BCP/Graham Holdings L.L.C., Graham Holdings’ general partner, which will be cancelled) will be converted into the right to receive one share of Graham Packaging common stock, which share of Graham Packaging common stock will then be converted into the right to receive the merger consideration in connection with the merger of Graham Packaging with and into Silgan. See “The Merger Agreement—Graham Holdings Merger and Subsequent Transactions” beginning on page 106.

In addition, immediately following the effective time of the merger of Graham Packaging with and into Silgan, Silgan will, in immediately successive steps:

We refer to the foregoing steps, collectively, as the “subsequent transactions.”

Effect of the Merger on Graham Packaging’s Equity Awards (page 107)

At the effective time of the merger, each outstanding option to purchase shares of Graham Packaging common stock will, whether or not then exercisable or vested, be converted into an option to purchase Silgan common stock in accordance with the terms of the merger agreement. In connection with the Graham Holdings merger, each outstanding option to purchase Graham Holdings’ partnership units under Graham Holdings’ equity-based compensation plans, whether or not then exercisable, will be assumed by Graham Packaging and converted into an option to purchase a number of shares of Graham Packaging common stock equal to the number of Graham Holdings’ partnership units subject to the option. These converted Graham Holdings’ options will also be converted into an option to purchase Silgan common stock in connection with the merger of Graham Packaging with and into Silgan.

The terms and conditions of each Graham Packaging stock option (including former Graham Holdings’ options converted into Graham Packaging options) converted into an option to purchase Silgan common stock at the effective time of the merger will remain the same as the terms and conditions that were in effect immediately prior to the effective time with respect to such Graham Packaging stock option, except that:

The “Option Exchange Ratio” is the sum of (a) 0.402 and (b) the quotient of $4.75 divided by the per share closing price of Silgan common stock on the NASDAQ on the last trading day immediately prior to the date on which the merger becomes effective. Some Graham Packaging stock options (including former Graham Holdings’ options converted into Graham Packaging options) will vest as a result of the merger and remain vested following conversion to options to purchase Silgan common stock.

In connection with the execution of the merger agreement, the board of directors of Graham Packaging approved the amendment of multiple of invested capital, which we refer to as “MOIC,” vesting options granted in 2006 and 2009 to Graham Packaging’s chief executive officer and in 2009 to Graham Packaging’s chief financial officer to provide upon consummation of the merger that such options will vest with respect to 25% of the shares covered by such options, but only if such individuals continue to provide services to Graham Packaging through consummation of the merger. In addition, the vesting criteria for the remaining 75% of shares

covered by such options will be amended so that vesting is based solely upon the MOIC achieved by Blackstone Capital, Blackstone Offshore Capital Partners III L.P. and their affiliates in a complete sale of their interest in Silgan relative to the Blackstone Entities’ original invested capital in Graham Packaging, regardless of whether the optionholder provides services to Silgan at the time of such sale.

Financing Relating to the Merger (page 93)

Silgan has received financing commitments from each of Bank of America, N.A., Deutsche Bank AG New York Branch, Citigroup Global Markets Inc., Citibank, N.A., Citicorp USA, Inc. and Citicorp North America, Inc., and Wells Fargo Bank, N.A., subject to customary conditions, for a proposed new $900 million term loan A facility, $2.3 billion term loan B facility (which, at the option of Silgan and the commitment parties, may be replaced by one or more senior note facilities that will reduce the principal amount of the term loan B facility on a dollar for dollar basis), $800 million revolving credit facility and a $900 million bridge facility. Silgan currently expects to use the newly committed $4.0 billion senior secured credit facility, the issuance of $400 million of senior subordinated notes and existing cash balances to fund the cash portion of the merger consideration and refinance certain of Silgan’s and Graham Packaging’s existing debt. Graham Packaging will cooperate with Silgan’s efforts to secure the financing and Silgan will reimburse Graham Packaging for the expenses it incurs in performing those efforts.

Silgan is obligated under the merger agreement to use its reasonable best efforts to take all actions and to do all things necessary, proper or advisable to consummate and obtain financing on the terms and conditions described in the amended and restated commitment letter that it entered into with Bank of America, N.A. and Merrill Lynch, Pierce, Fenner & Smith Incorporated in connection with the merger agreement (which we refer to as the “commitment letter”). Upon the terms and subject to the conditions set forth in the merger agreement, Silgan may from time to time amend, replace, supplement or otherwise modify, or waive any of its rights under the commitment letter, including to add additional lenders, agents or other parties to the commitment letter and/or substitute other debt (but not equity financing) for all or any portion of the financing of the merger from the same and/or alternative financing sources. Silgan’s ability to obtain financing is not a condition precedent to the merger.

For a full description of financing relating to the merger, see “The Merger—Financing Relating to the Merger,” on page 93.

Silgan’s Reasons for the Merger (page 53)

In evaluating the merger, the Silgan board of directors consulted with members of Silgan’s management and Silgan’s advisors regarding, among other things, the past and current business operations, financial condition and future prospects of Graham Packaging, the strategic, governance and operational aspects of combining Silgan and Graham Packaging and financial and legal aspects of the transaction and, in reaching its decision to approve the merger agreement and the transactions contemplated thereby and to recommend that Silgan stockholders adopt the merger agreement, the Silgan board of directors considered a number of factors, including those listed in “The Merger—Silgan’s Reasons for the Merger and Recommendation of Silgan’s Board of Directors” beginning on page 53.

Graham Packaging’s Reasons for the Merger (page 57)

In evaluating the merger, the Graham Packaging board of directors consulted with members of Graham Packaging’s management and Graham Packaging’s advisors regarding, among other things, the past and current business operations, financial condition and future prospects of Silgan, the strategic, governance and operational aspects of combining Silgan and Graham Packaging and financial and legal aspects of the transaction and, in reaching its decision to approve the merger agreement and the transactions contemplated thereby and to recommend that Graham Packaging stockholders adopt the merger agreement, acting upon the unanimous

recommendation of the special committee, the Graham Packaging board of directors considered a number of factors, including those listed in “The Merger—Graham Packaging’s Reasons for the Merger and Recommendation of Graham Packaging’s Board of Directors” beginning on page 57.

Recommendations of the Boards of Directors to Silgan Stockholders and Graham Packaging Stockholders (page 53 for Silgan Stockholders and page 57 for Graham Packaging Stockholders)

Silgan Stockholders. The Silgan board of directors has unanimously determined that the merger agreement and the transactions contemplated thereby, including the merger, are advisable and fair to, and in the best interests of, Silgan and its stockholders and has unanimously approved the merger agreement and the transactions contemplated thereby, including the merger. The Silgan board of directors has resolved to recommend that Silgan stockholders vote FOR the adoption of the merger agreement. Approval of the adoption of the merger agreement by Silgan stockholders will also constitute approval of the issuance of Silgan common stock to Graham Packaging stockholders in the merger and approval of Silgan’s amended and restated certificate of incorporation.

Graham Packaging Stockholders. The Graham Packaging board of directors, acting upon the unanimous recommendation of the special committee, has unanimously determined that the merger agreement and the transactions contemplated thereby, including the merger, are advisable and fair to, and in the best interests of, Graham Packaging and its stockholders and has unanimously approved the merger agreement and the transactions contemplated thereby, including the merger. The Graham Packaging board of directors has resolved to recommend that Graham Packaging stockholders vote FOR the adoption of the merger agreement.

Opinions of Financial Advisors (page 60 for Silgan’s financial advisor and page 68 for Graham Packaging’s financial advisor)

Opinion of Silgan’s Financial Advisor

In connection with the merger, Merrill Lynch, Pierce, Fenner & Smith Incorporated (which we refer to as “BofA Merrill Lynch”), Silgan’s financial advisor, delivered to the Silgan board of directors an oral opinion on April 11, 2011, subsequently confirmed on, and delivered in writing dated, April 12, 2011, as to the fairness, from a financial point of view and as of the date of the opinion, to Silgan of the merger consideration to be paid by Silgan in the merger. The full text of the written opinion, dated April 12, 2011, of BofA Merrill Lynch, which describes, among other things, the assumptions made, procedures followed, factors considered and limitations on the review undertaken, is attached as Annex B to this joint proxy statement/prospectus and is incorporated by reference herein in its entirety. BofA Merrill Lynch provided its opinion to the Silgan board of directors (in its capacity as such) for the benefit and use of the Silgan board of directors in connection with and for purposes of its evaluation of the merger consideration from a financial point of view. BofA Merrill Lynch’s opinion does not address any other aspect of the merger and no opinion or view was expressed as to the relative merits of the merger in comparison to other strategies or transactions that might be available to Silgan or in which Silgan might engage or as to the underlying business decision of Silgan to proceed with or effect the merger. BofA Merrill Lynch’s opinion does not constitute a recommendation to any stockholder as to how to vote or act in connection with the proposed merger or any related matter.

Opinion of Graham Packaging’s Financial Advisor

J.P. Morgan Securities LLC, which we refer to as “J.P. Morgan,” was retained by the special committee to act as its financial advisor in connection with a potential strategic transaction. On April 12, 2011, J.P. Morgan rendered its oral opinion, subsequently confirmed by delivery of a written opinion dated April 12, 2011, to the special committee and, with the approval of the special committee and at its direction, to the full Graham Packaging board of directors to the effect that, as of that date and based upon and subject to the factors, assumptions and limitations described in its written opinion, the merger consideration to be paid to the holders of Graham Packaging common stock (other than Donald C. Graham and certain entities controlled by Donald C.

Graham and his family, which we refer to collectively as the “Graham family,” and the Blackstone Entities) was fair, from a financial point of view, to such holders. With the approval of the special committee and at its direction, the J.P. Morgan written opinion was provided to and relied upon by the full Graham Packaging board of directors.

The full text of the written opinion of J.P. Morgan, dated April 12, 2011, which is attached to this joint proxy statement/prospectus as Annex C, sets forth the assumptions made, procedures followed, matters considered and limitations on the review undertaken by J.P. Morgan in rendering its opinion. The summary of J.P. Morgan’s opinion in this joint proxy statement/prospectus is qualified in its entirety by reference to the full text of its written opinion. J.P. Morgan’s opinion is directed to the special committee, addresses only the fairness, from a financial point of view, of the merger consideration to be received by the holders of common stock of Graham Packaging (other than the Graham family and the Blackstone Entities) in the proposed merger, and does not address any other aspect of the merger. The issuance of the J.P. Morgan opinion was approved by a fairness opinion committee of J.P. Morgan. J.P. Morgan provided its advisory services and opinion for the information and assistance of the special committee in connection with the special committee’s consideration of the proposed merger. The opinion of J.P. Morgan does not constitute a recommendation as to how any stockholder should vote with respect to the proposed merger. In addition, the J.P. Morgan opinion does not in any manner address the prices at which Graham Packaging’s or Silgan’s common stock will trade following the date of the opinion. See “The Merger—Opinion of Graham Packaging’s Financial Advisor” beginning on page 68.

Comparative Market Value Information (page 31)

The following table presents the closing prices per share of Silgan common stock and Graham Packaging common stock, as reported by the NASDAQ and the NYSE, respectively, on April 12, 2011, the last trading day prior to the announcement of the merger, and [—], 2011, the last practicable day prior to the date of this joint proxy statement/prospectus. This table also presents the implied value of the merger consideration for each share of Graham Packaging common stock, calculated by adding the cash portion of the merger consideration of $4.75 to the product of the closing price of Silgan common stock multiplied by 0.402, the exchange ratio.

Record Date; Outstanding Shares; Shares Entitled to Vote (page 133 for Silgan and page 138 for Graham Packaging)

Silgan Stockholders. The record date for the Silgan special meeting is [—], 2011. This means that you must be a stockholder of record of Silgan common stock at the close of business on [—], 2011, in order to vote at the Silgan special meeting. You are entitled to one vote for each share of Silgan common stock you own. At the close of business on [—], 2011, there were [—] shares of Silgan common stock outstanding and entitled to vote at the Silgan special meeting. A majority of the shares of Silgan common stock outstanding at the close of business on the record date and entitled to vote, present in person or represented by proxy, at the special meeting constitutes a quorum for purposes of the special meeting.

Graham Packaging Stockholders. The record date for the Graham Packaging special meeting is [—], 2011. This means that you must be a stockholder of record of Graham Packaging common stock at the close of business on [—], 2011 in order to vote at the Graham Packaging special meeting. You are entitled to one vote for each share of Graham Packaging common stock you own. As of the record date, there were [—] shares of Graham Packaging common stock outstanding and entitled to vote at the Graham Packaging special meeting. A majority

of the shares of Graham Packaging common stock outstanding at the close of business on the record date and entitled to vote, present in person or represented by proxy, at the special meeting constitutes a quorum for purposes of the special meeting.

Vote Required (page 133 for Silgan and page 138 for Graham Packaging)

Silgan. Approval of the proposal to adopt the merger agreement requires the affirmative vote of a majority of the outstanding shares of Silgan common stock entitled to vote at the special meeting. Approval of the proposal to adjourn the special meeting requires the affirmative vote of not less than a majority of the votes cast by the holders of shares of Silgan common stock. As more fully described in “Voting Agreements—Voting Agreements with respect to shares of Silgan Common Stock” beginning on page 127, the Co-Founders and their affiliates have entered in voting agreements with Graham Packaging pursuant to which they have agreed, subject to certain exceptions, to vote all of their beneficially owned shares of Silgan common stock, or approximately 29% of the total outstanding shares of Silgan common stock as of April 12, 2011, in favor of the proposal to adopt the merger agreement.

Graham Packaging. Approval of the proposal to adopt the merger agreement requires the affirmative vote of a majority of the outstanding shares of Graham Packaging common stock entitled to vote at the special meeting. Approval of the proposal to adjourn the special meeting and approval of the advisory vote of Graham Packaging stockholders on the compensation that may be received by Graham Packaging named executive officers in connection with the merger require the affirmative vote of at least a majority of the voting power of the issued and outstanding shares of Graham Packaging common stock present in person or represented by proxy and entitled to vote thereon. This proposal is advisory in nature and will not be binding on Graham Packaging or the Graham Packaging board of directors. As more fully described in “Voting Agreements—Voting Agreement with respect to shares of Graham Packaging Common Stock” beginning on page 126, the Blackstone Entities have entered into a voting agreement with Silgan pursuant to which they have agreed, subject to certain exceptions, to vote all of their beneficially owned shares of Graham Packaging common stock, or approximately 61% of the total outstanding shares of Graham Packaging common stock as of April 12, 2011, in favor of the proposal to adopt the merger agreement, which is a sufficient number of shares to adopt the merger agreement.

Stock Ownership of Directors and Executive Officers (page 86)

Silgan. At the close of business on [—], 2011, the directors and executive officers of Silgan beneficially owned and were entitled to vote [—] shares of Silgan common stock, collectively representing approximately [—]% of the shares of Silgan common stock outstanding on that date.

Graham Packaging. At the close of business on [—], 2011, the directors and executive officers of Graham Packaging beneficially owned and were entitled to vote [—] shares of Graham Packaging common stock, collectively representing approximately [—]% of the shares of Graham Packaging common stock outstanding on that date.

Interests of Graham Packaging Directors and Executive Officers in the Merger (page 87)

Graham Packaging’s executive officers and directors have financial interests in the merger that are different from, or in addition to, the interests of Graham Packaging stockholders. These interests include rights of executive officers under change of control agreements with Graham Packaging, rights under a severance plan and under equity compensation awards of Graham Packaging, rights to continued indemnification and insurance

coverage by Silgan after the merger for acts or omissions occurring before the merger, and the affiliation of certain directors with the Blackstone Entities. The Graham Packaging board of directors and the special committee were aware of these interests and considered them in their decision to approve the merger agreement.

Board of Directors and Management of Silgan Following the Merger (page 91)

At the effective time of the merger, the directors and officers of Silgan will continue as the directors and officers of the surviving corporation. Additionally, in accordance with Silgan’s amended and restated certificate of incorporation to be approved by the Silgan stockholders in connection with the merger, the size of the Silgan board of directors will be increased from seven directors to nine directors. Consequently, immediately following the effective time of the merger, the Silgan board of directors will be comprised of the seven current directors and two additional directors to be appointed to fill the vacancies created by the increase in the size of the board of directors. As more fully described in “Ancillary Agreements—Stockholders Agreement and Letter Agreement” beginning on page 130, one additional director, to be appointed as a Class I director, will be a designee of Blackstone Capital, which designee must be reasonably satisfactory to the Co-Founders, pursuant to the new stockholders agreement. Silgan anticipates that the second additional director, to be appointed as a Class II director, will be an independent director. Each of the two additional directors will be nominated by the Co-Founders, pursuant to the Co-Founders’ nomination rights under the existing stockholders agreement, and appointed by the majority of the board of directors, to fill the vacancies created by the increase in the size of the Silgan board of directors in accordance with Silgan’s amended and restated certificate of incorporation. Pursuant to the terms of the letter agreement, which is more fully described in “Ancillary Agreements—Stockholders Agreement and Letter Agreement” beginning on page 130, Silgan has agreed to take all necessary action to cause the Blackstone Capital designee to be appointed as a Class I director to fill the applicable vacancy effective as of the first day immediately following the date on which the effective time of the merger occurs.

Listing of Silgan Common Stock and De-listing of Graham Packaging Common Stock (page 91)

It is a condition to the merger that the shares of common stock to be issued by Silgan in connection with the merger be authorized for listing on the NASDAQ subject to official notice of issuance. Shares of Silgan common stock are currently traded on the NASDAQ under the symbol “SLGN.” Shares of Graham Packaging common stock are currently traded on the NYSE under the symbol “GRM.” If the merger is completed, Graham Packaging common stock will no longer be listed on the NYSE and will be deregistered under the Securities Exchange Act of 1934, as amended, which we refer to as the “Exchange Act,” and Graham Packaging will no longer file periodic reports with the SEC.

Appraisal Rights (page 95)

Graham Packaging stockholders have the right under Delaware law to dissent from the adoption of the merger agreement, to exercise appraisal rights and to receive payment in cash of the judicially determined fair value for their shares, plus interest, if any, on the amount determined to be the fair value, in accordance with Delaware law. The fair value of shares of Graham Packaging common stock, as determined in accordance with Delaware law, may be more or less than, or equal to, the merger consideration to be paid to non-dissenting stockholders in the merger. To preserve their rights, Graham Packaging stockholders who wish to exercise appraisal rights must not vote in favor of the proposal to adopt the merger agreement and must follow the specific procedures provided under Delaware law for perfecting appraisal rights. Dissenting stockholders must precisely follow these specific procedures to exercise appraisal rights or their appraisal rights may be lost. These procedures are described in this joint proxy statement/prospectus, and a copy of Section 262 of the DGCL, which we refer to as “Section 262,” which grants appraisal rights and governs such procedures, is attached as Annex D to this joint proxy statement/prospectus. See “The Merger—Graham Packaging Stockholders’ Rights of Appraisal” beginning on page 95. Appraisal rights are not available to holders of Silgan common stock.

Silgan’s Dividend Policy (page 93)

Since 2004, Silgan has paid quarterly dividends to its stockholders and last paid a dividend on March 17, 2011 of $0.11 per share. Silgan currently intends to continue to pay quarterly dividends to its stockholders following the merger; however, the payment of dividends by Silgan after the merger will be subject to the determination of the Silgan board of directors. As has been the practice in the past, decisions by the Silgan board of directors regarding whether or not to pay dividends on Silgan common stock and the amount of any dividends will be based on compliance with the DGCL, compliance with agreements governing Silgan’s indebtedness, earnings, cash requirements, results of operations, cash flows and financial condition and other factors that the Silgan board of directors considers important. Under the terms of the merger agreement, prior to the effective time of the merger or termination of the merger agreement, Silgan may continue to pay its regular quarterly dividends, with usual amounts, declaration, record and payment dates and otherwise consistent with past practice.

Conditions to Completion of the Merger (page 120)

The obligations of each of Silgan and Graham Packaging to complete the merger are subject to the satisfaction or waiver on or prior to the closing date of the merger of the following conditions:

We cannot be certain when, or if, the conditions to the merger will be satisfied or, where permissible, waived, or that the merger will be completed. Approval of the “golden parachute” compensation payable to certain officers of Graham Packaging in the nonbinding advisory vote described in this joint proxy statement/prospectus is not a condition to completion of the merger.

Regulatory Approvals Required for the Merger (page 92)

The completion of the merger is subject to compliance with the HSR Act and receipt of certain foreign antitrust approvals. The notifications required under the HSR Act to the U.S. Federal Trade Commission (which we refer to as the “FTC”) and the Antitrust Division of the U.S. Department of Justice (which we refer to as the

“Antitrust Division”) were filed on April 26, 2011. The waiting period under the HSR Act expired at 11:59 p.m., Eastern Daylight Time, on May 26, 2011. In addition, all necessary filings have been submitted with respect to the aforementioned foreign antitrust approvals.

Silgan has agreed, if action is necessary to prevent the commencement of any proceeding by any governmental entity that would delay, enjoin or otherwise prohibit consummation of the merger, that it will take such action (including with respect to selling, holding separate or otherwise disposing of any business or assets, or agreeing to any conditions or restrictions) as may be necessary to prevent the commencement of such proceeding.

Takeover Proposals (page 113)

The merger agreement provides that Graham Packaging will not, directly or indirectly, solicit, initiate or knowingly encourage or knowingly facilitate any takeover proposal (as defined on page 115) or enter into any discussions or negotiations regarding, or enter into any agreement with respect to, any takeover proposal. Graham Packaging has agreed to immediately cease all activities with any party with respect to any takeover proposal existing at the time the merger agreement was entered into.

However, if Graham Packaging receives an unsolicited takeover proposal and Graham Packaging’s special committee or the Graham Packaging board of directors, acting upon the recommendation of Graham Packaging’s special committee, determines in good faith that (A) such takeover proposal constitutes or could reasonably be expected to lead to a superior proposal (as defined on page 115) and (B) the failure to provide non-public information or enter into discussions or negotiations with such third party would be inconsistent with Graham Packaging’s directors’ fiduciary duties, Graham Packaging may, under certain circumstances, furnish information to such third party and participate in discussions or negotiations regarding such takeover proposal. Graham Packaging has agreed to notify Silgan promptly in the event that it receives any takeover proposal.

The special committee or the Graham Packaging board of directors may make a Graham Packaging adverse recommendation change (as defined on page 115) under certain circumstances in response to a takeover proposal if the special committee or the Graham Packaging board of directors, acting upon the recommendation of the special committee, concludes in good faith that (1) such takeover proposal would, if consummated, constitute a superior proposal and (2) the failure to take such action would be inconsistent with the directors’ fiduciary duties. However, neither the Graham Packaging board of directors nor the special committee shall make a Graham Packaging adverse recommendation change or terminate the merger agreement unless Graham Packaging notifies Silgan in writing, at least three business days before taking such action, of its intention to do so, and negotiates with Silgan in good faith during such three business day period to make adjustments to the terms and conditions of the merger agreement so that the special committee or the Graham Packaging board of directors, acting upon the recommendation of the special committee, determines in good faith that such takeover proposal ceases to constitute a superior proposal.

Termination of the Merger Agreement (page 122)

The merger agreement may be terminated at any time before the effective time of the merger, whether before or after the Silgan stockholders and/or the Graham Packaging stockholders have adopted the merger agreement (except in limited circumstances described below):

Termination Fees and Expenses (page 123)

If the merger agreement is terminated in certain circumstances described under “The Merger Agreement — Termination of the Merger Agreement” beginning on page 122:

In addition, in the event that the Silgan stockholders do not adopt the merger agreement, Silgan has agreed to pay to Graham Packaging an amount equal to $12 million. If such $12 million payment is made by Silgan, then the termination fee, if any, later paid by Silgan would be reduced by such $12 million payment previously paid. In addition, in the event of a termination of the merger agreement as a result of a material breach of the merger agreement, a non-terminating party may be required to reimburse the terminating party for certain fees and expenses, up to an aggregate maximum amount of $12 million.

Litigation Related to the Merger (page 92)

Silgan and Graham Packaging are aware of one lawsuit relating to the merger filed by a purported stockholder of Graham Packaging against Graham Packaging, Graham Packaging’s directors and Silgan. The purported class action alleges, among other things, that the directors of Graham Packaging have breached their fiduciary duties to the Graham Packaging stockholders and that Graham Packaging and Silgan aided and abetted Graham Packaging’s directors’ alleged breaches of their fiduciary duties. The plaintiff seeks, among other things, injunctive relief preventing the defendants from consummating the merger. Graham Packaging, Silgan and the other defendants believe that the lawsuit is without merit and intend to defend the action vigorously.

Material United States Federal Income Tax Consequences (page 99)

The merger is intended to qualify for U.S. federal income tax purposes as a “reorganization” within the meaning of Section 368(a) of the Code. Therefore, for U.S. federal income tax purposes, as a result of the merger, a U.S. holder of shares of Graham Packaging common stock generally will only recognize gain (but not loss) in an amount not to exceed the cash received as part of the merger consideration and will recognize gain or loss with respect to any cash received in lieu of fractional shares of Silgan common stock. You should read “Material United States Federal Income Tax Consequences” beginning on page 99 for a more complete discussion of the U.S. federal income tax consequences of the transaction.

Accounting Treatment (page 98)

The merger will be accounted for under the acquisition method of accounting in conformity with U.S. generally accepted accounting principles (which we refer to as “GAAP”), for accounting and financial reporting purposes.

Risk Factors (page 32)

In evaluating the merger and the merger agreement, you should read carefully this joint proxy statement/prospectus and especially consider the factors discussed in the section titled “Risk Factors” beginning on page 32.

Comparison of Rights of Stockholders (page 151)

As a result of the merger, the holders of Graham Packaging common stock will become holders of Silgan common stock and their rights will be governed by the DGCL and by Silgan’s certificate of incorporation and by-laws. Following the merger, Graham Packaging stockholders may have different rights as stockholders of Silgan than as stockholders of Graham Packaging. For a summary of the material differences between the rights of Graham Packaging stockholders and Silgan stockholders, see “Comparison of Rights of Stockholders” beginning on page 151.

FINANCIAL SUMMARY

Comparative Market Price Data and Dividends

Silgan common stock is traded on the NASDAQ under the symbol “SLGN” and Graham Packaging common stock is traded on the NYSE under the symbol “GRM.” The following table shows the high and low daily closing sales prices per share during the period indicated for Silgan on the NASDAQ and Graham Packaging common stock on the NYSE. Closing sales prices and cash dividends per share for Silgan common stock have been retroactively adjusted for the two-for-one stock split of Silgan common stock that occurred on May 3, 2010. For current price information, you are urged to consult publicly available sources.

Silgan currently intends to continue to pay quarterly dividends to its stockholders following the merger, however, the payment of dividends by Silgan after the merger will be subject to the determination of the Silgan board of directors. As has been the practice in the past, decisions by the Silgan board of directors regarding whether or not to pay dividends on Silgan common stock and the amount of any dividends will be based on compliance with the DGCL, compliance with agreements governing Silgan’s indebtedness, earnings, cash requirements, results of operations, cash flows and financial condition and other factors that the Silgan board of directors considers important. Under the terms of the merger agreement, prior to the effective time of the merger or termination of the merger agreement, Silgan may continue to pay its regular quarterly dividends, with usual amounts, declaration, record and payment dates and otherwise consistent with past practice.

The Graham Packaging board of directors has the power to determine the amount and frequency of the payment of dividends. Decisions regarding whether to pay dividends and the amount of any dividends are based upon compliance with the DGCL, compliance with agreements governing Graham Packaging’s indebtedness, earnings, cash requirements, results of operations, cash flows, financial condition and other factors that the board of directors considers important. While Graham Packaging anticipates that if the merger were not consummated it would continue not to pay dividends, it cannot assure that will be the case. Under the merger agreement, until the effective time or termination of the merger agreement, Graham Packaging will not declare, set aside or pay any dividends on, or make any other distributions in respect of, any of its capital stock or otherwise make any payments to its stockholders in their capacity as such.

Selected Historical Consolidated Financial Data of Silgan

The following table shows selected historical financial data for Silgan. The selected financial data as of December 31, 2010, 2009, 2008, 2007 and 2006, and for each of the five years then ended were derived from the audited historical consolidated financial statements and related footnotes of Silgan. The selected financial data as of March 31, 2011 and 2010, and for each of the three months then ended were derived from the unaudited historical consolidated financial statements and related footnotes of Silgan.

Detailed historical financial information included in the audited consolidated balance sheets as of December 31, 2010 and 2009, and the consolidated statements of income, stockholders’ equity, cash flows and related notes for each of the years in the three-year period ended December 31, 2010, are included in Silgan’s Annual Report on Form 10-K for the fiscal year ended December 31, 2010 and incorporated by reference in this joint proxy statement/prospectus. Detailed historical financial information included in the unaudited consolidated financial statements for each of the quarterly periods ended March 31, 2011 and 2010 are included in Silgan’s Quarterly Report on Form 10-Q for the period ended March 31, 2011. You should read the following selected financial data together with Silgan’s historical consolidated financial statements, including the related notes, and the other information contained or incorporated by reference in this joint proxy statement/prospectus. See “Where You Can Find More Information” beginning on page 187.

Silgan Selected Financial Data