Exhibit 99.(12)

	ROPES & GRAY LLP
	PRUDENTIAL TOWER
	800 BOYLSTON STREET
	BOSTON, MA 02199-3600
	WWW.ROPESGRAY.COM

August 29, 2025

Calamos Growth and Income Fund

Calamos Investment Trust

2020 Calamos Court

Naperville, IL 60563

Calamos Dividend Growth Fund

Calamos Investment Trust

2020 Calamos Court

Naperville, IL 60563

Ladies and Gentlemen:

We have acted as counsel in connection with the Agreement and Plan of Reorganization (the “Agreement”) dated August 25, 2025, by and between Calamos Investment Trust, a Massachusetts business trust (the “Trust”), on behalf of one of its series, Calamos Dividend Growth Fund (“Target Fund”), and the Trust on behalf of one of its series, Calamos Growth and Income Fund (“Acquiring Fund”). The Agreement describes a proposed transaction (the “Reorganization”) to occur as of the date of this letter (the “Closing Date”), pursuant to which Acquiring Fund will acquire all of the assets of Target Fund in exchange for shares of beneficial interest in Acquiring Fund (the “Acquiring Fund Shares”) and the assumption by Acquiring Fund of all of the liabilities of Target Fund following which the Acquiring Fund Shares received by Target Fund will be distributed by Target Fund to its shareholders in liquidation and termination of Target Fund. This opinion as to certain U.S. federal income tax consequences of the Reorganization is furnished to you pursuant to Section 6.3(e) of the Agreement. Capitalized terms not defined herein are used herein as defined in the Agreement.

Target Fund is a series of the Trust, which is registered under the Investment Company Act of 1940, as amended, as an open-end management investment company. Shares of Target Fund are redeemable at net asset value at each shareholder’s option. Target Fund has elected to be a regulated investment company for federal income tax purposes under Section 851 of the Internal Revenue Code of 1986, as amended (the “Code”).

Acquiring Fund also is a series of the Trust. Shares of Acquiring Fund are redeemable at net asset value at each shareholder’s option. Acquiring Fund has elected to be a regulated investment company for federal income tax purposes under Section 851 of the Code.

For purposes of this opinion, we have considered the Agreement, the Combined Registration/Proxy Statement dated July 2, 2025, and such other items as we have deemed necessary to

Calamos Growth and Income Fund	August 29, 2025
Calamos Dividend Growth Fund

render this opinion. In addition, each of Target Fund and Acquiring Fund has provided us with a letter dated as of the date hereof (collectively, the “Representation Letters”) representing as to certain facts, occurrences and information upon which each of Target Fund and Acquiring Fund has indicated that we may rely in rendering this opinion (whether or not contained or reflected in the documents and items referred to above).

In reviewing the foregoing materials, we have assumed, with your permission, the authenticity of original documents, the accuracy of copies, the genuineness of signatures, the legal capacity of signatories, and the proper execution of documents. We have further assumed that (i) all parties to the Agreement and any other documents examined by us have acted, and will act, in accordance with the terms of such Agreement and documents, and that the Reorganization will be consummated pursuant to the terms and conditions set forth in the Agreement without the waiver or modification of any such terms and conditions; and (ii) all representations contained in the Agreement, as well as those representations contained in the Representation Letters, are true and complete.

Based on and subject to the foregoing and subject to the final paragraphs hereof, we are of the opinion that, for U.S. federal income tax purposes:

(i) The Reorganization will constitute a “reorganization” within the meaning of Section 368(a) of the Code, and Acquiring Fund and Target Fund each will be “a party to a reorganization” within the meaning of Section 368(b) of the Code;

(ii) Under Sections 361 and 357(a) of the Code, Target Fund will not recognize gain or loss upon the transfer of Target Fund’s assets to Acquiring Fund in exchange for Acquiring Fund Shares and the assumption by Acquiring Fund of all the liabilities of Target Fund, or upon the distribution of Acquiring Fund Shares by Target Fund to its shareholders in liquidation, except for (A) any gain or loss recognized on (1) “section 1256 contracts” as defined in Section 1256(b) of the Code or (2) stock in a “passive foreign investment company” as defined in Section 1297(a) of the Code, and (B) any other gain or loss that may be required to be recognized (1) as a result of the closing of the tax year of Target Fund, (2) upon the termination of a position, or (3) upon the transfer of an asset regardless of whether such a transfer would otherwise be a nontaxable transaction under the Code;

(iii) Under Section 354 of the Code, Target Fund shareholders will not recognize any gain or loss upon the exchange of their Target Fund shares for Acquiring Fund Shares in the Reorganization;

(iv) Under Section 358 of the Code, the aggregate tax basis of Acquiring Fund Shares a Target Fund shareholder receives in the Reorganization will be the same as the aggregate tax basis of the Target Fund shares exchanged therefor;

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Calamos Dividend Growth Fund

(v) Under Section 1223(1) of the Code, an Target Fund shareholder’s holding period for the Acquiring Fund Shares received in the Reorganization will be determined by including the period during which such shareholder held or is treated for federal income tax purposes as having held the Target Fund shares exchanged therefor, provided that the shareholder held those Target Fund shares as capital assets;

(vi) Under Section 1032 of the Code, Acquiring Fund will not recognize gain or loss upon the receipt of the assets of Target Fund in exchange for Acquiring Fund Shares and the assumption by Acquiring Fund of all the liabilities of Target Fund;

(vii) Under Section 362(b) of the Code, Acquiring Fund’s tax basis in the assets of Target Fund transferred to Acquiring Fund in the Reorganization will be the same as Target Fund’s tax basis immediately prior to the transfer, increased by any gain or decreased by any loss required to be recognized as described in (ii) above;

(viii) Under Section 1223(2) of the Code, the holding period in the hands of Acquiring Fund of each Target Fund asset transferred to Acquiring Fund in the Reorganization, other than certain assets with respect to which gain or loss is required to be recognized as described in (ii) above, will include the period during which such asset was held or treated for federal income tax purposes as held by Target Fund; and

(ix) Acquiring Fund will succeed to and take into account the items of Target Fund described in Section 381(c) of the Code, subject to the conditions and limitations specified in Sections 381, 382, 383 and 384 of the Code and the Regulations thereunder.

We believe that Acquiring Fund will continue Target Fund’s historic business, within the meaning of Treas. Reg. § 1.368-1(d), as an open-end management investment company that seeks high long-term total return by investing in equity securities and that the continuity of business enterprise test required for qualification under Section 368(a) of the Code is met in the Reorganization.

No ruling has been or will be obtained from the Internal Revenue Service (“IRS”) as to the subject matter of this opinion and there can be no assurance that the IRS or a court of law will concur with the opinion set forth above. Our opinion is based on the Code, Treasury Regulations, IRS rulings, judicial decisions, and other applicable authority, all as in effect on the date of this opinion. The legal authorities on which this opinion is based may be changed at any time. Any such changes may be retroactively applied and could modify the opinions expressed above.

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Calamos Growth and Income Fund	August 29, 2025
Calamos Dividend Growth Fund

Very truly yours,

/s/ Ropes & Gray LLP

Ropes & Gray LLP

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