Perma-Fix major holder reports 5.5% stake

Perma-Fix Environmental Services, Inc. has a significant shareholder group led by MAK Capital Fund LP, MAK Capital One L.L.C., and Michael A. Kaufman.

Rhea-AI Filing Summary

Perma-Fix Environmental Services, Inc. has a significant shareholder group led by MAK Capital Fund LP, MAK Capital One L.L.C., and Michael A. Kaufman. These reporting persons collectively report beneficial ownership of 1,161,372 shares of Perma-Fix common stock.

This position represents 5.5% of the outstanding common stock, based on 21,203,552 shares outstanding as of May 28, 2026. The group reports no sole voting or dispositive power, but shared voting and shared dispositive power over all 1,161,372 shares, indicating coordinated control over how this block is voted and potentially sold.

Key Figures

Shares beneficially owned: 1,161,372 shares Percent of class: 5.5% Shares outstanding: 21,203,552 shares +4 more

7 metrics

Shares beneficially owned 1,161,372 shares Beneficially owned by MAK Capital Fund LP, MAK Capital One L.L.C., and Michael A. Kaufman as of 08/06/2026

Percent of class 5.5% Portion of Perma-Fix common stock represented by 1,161,372 shares

Shares outstanding 21,203,552 shares Perma-Fix common stock outstanding as of May 28, 2026, used for ownership calculation

Sole voting power 0 shares Shares over which the reporting persons have sole voting power

Shared voting power 1,161,372 shares Shares over which the reporting persons have shared power to vote or direct the vote

Sole dispositive power 0 shares Shares over which the reporting persons have sole dispositive power

Shared dispositive power 1,161,372 shares Shares over which the reporting persons have shared power to dispose or direct disposition

Key Terms

beneficially owned, shared voting power, dispositive power, Schedule 13G, +1 more

5 terms

beneficially owned financial

"The calculation is based upon 1,161,372 shares of Common Stock beneficially owned"

Beneficially owned describes securities or assets where a person has the economic rights and control—such as the right to receive dividends and to direct voting—even if legal title is held in another name. Think of it like having the keys and using a car that’s registered to someone else: you get the benefits and make decisions. Investors care because beneficial ownership reveals who truly controls value and voting power, affecting corporate decisions and takeover dynamics.

shared voting power financial

"Shared Voting Power 1,161,372.00"

Shared voting power occurs when two or more parties jointly have the right to vote or decide how a block of company shares is cast, like co-owners who must agree before moving a piece of furniture. Investors care because who controls voting rights affects board elections, major corporate decisions and takeover outcomes, and shared control can alter regulatory disclosures and the practical influence any holder has over a company’s direction and value.

dispositive power financial

"Shared Dispositive Power 1,161,372.00"

Dispositive power is the authority to decide the final outcome of an asset, legal claim, contract, or corporate action — in effect the power to dispose of or resolve something. For investors it matters because whoever holds that authority can determine who gets paid, who controls an asset or vote, and how risks and returns are allocated; think of it like holding the key that lets you lock in the winner or loser in a deal.

Schedule 13G regulatory

"as reported by the Issuer in its Definitive Proxy Statement on Schedule 14A"

A Schedule 13G is a formal document that investors file with the government when they acquire a large ownership stake in a company, usually for investment purposes rather than control. It helps keep the public informed about who owns significant parts of a company's shares, which can influence how the company is managed and how investors make decisions. Filing this schedule is important for transparency and understanding the ownership landscape of publicly traded companies.

percent of class financial

"Percent of class: 5.5%"

Percent of class is the portion of a specific category of securities—such as a company’s common shares, preferred shares, or a bond series—that takes part in or approves a corporate action (vote, consent, tender, etc.). Investors watch this number because it reveals how much support or opposition exists within that particular shareholder group; like counting how many members of a club back a proposal, it can determine whether a plan passes or how influence is distributed.

FAQ

AI-generated questions and answers. How Rhea-AI works. Not financial advice.

How much of Perma-Fix Environmental Services (PESI) stock do the MAK Capital group and Michael A. Kaufman own?

The reporting group beneficially owns 1,161,372 shares of Perma-Fix Environmental Services common stock, representing 5.5% of the outstanding shares based on the issuer’s reported share count.

What percentage of Perma-Fix Environmental Services (PESI) does the MAK Capital group control voting power over?

The reporting persons have shared voting power over 1,161,372 shares, equal to 5.5% of Perma-Fix’s common stock, and report no sole voting power over any shares.

How many Perma-Fix (PESI) shares were outstanding for this 5.5% ownership calculation?

The 5.5% ownership stake is calculated using 21,203,552 shares of Perma-Fix common stock outstanding as of May 28, 2026, as reported by the company in a proxy statement.

Do the MAK Capital entities or Michael A. Kaufman have sole dispositive power over Perma-Fix (PESI) shares?

No. The reporting persons disclose 0 shares with sole dispositive power and 1,161,372 shares with shared dispositive power, meaning decisions to sell or transfer are shared among them.

Who are the reporting persons in the Perma-Fix (PESI) Schedule 13G?

The Schedule 13G is filed jointly by MAK Capital Fund LP, MAK Capital One L.L.C., and Michael A. Kaufman, who together report beneficial ownership and shared voting and dispositive power over 1,161,372 shares.

As of what date is the MAK Capital group’s Perma-Fix (PESI) share ownership reported?

The beneficial ownership of 1,161,372 shares is stated as of August 6, 2026, using an outstanding share count as of May 28, 2026, from the issuer’s proxy statement.

AI-generated analysis. How Rhea-AI works. Not financial advice.

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

Available on EDGAR 08/06/2026 - 06:11 PM Accepted by SEC EDGAR 08/06/2026 - 06:10 PM Learn about SEC filing dates

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

PERMA FIX ENVIRONMENTAL SERVICES INC

(Name of Issuer)

Common Stock, $0.001 par value per share

(Title of Class of Securities)

714157203

(CUSIP Number)

07/31/2026

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

schemaVersion:

SCHEDULE 13G

CUSIP Number(s): 714157203

1

Names of Reporting Persons

MAK Capital Fund LP

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

BERMUDA

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 1,161,372.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 1,161,372.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

1,161,372.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.5 %

12

Type of Reporting Person (See Instructions)

PN

Comment for Type of Reporting Person: The calculation is based upon 1,161,372 shares of Common Stock beneficially owned as of 08/06/2026 and a total of 21,203,552 shares of Common Stock, $0.001 par value per share, outstanding as of May 28, 2026, as reported by the Issuer in its Definitive Proxy Statement on Schedule 14A filed with the Securities and Exchange Commission on June 12, 2026.

SCHEDULE 13G

CUSIP Number(s): 714157203

1

Names of Reporting Persons

MAK CAPITAL ONE LLC

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 1,161,372.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 1,161,372.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

1,161,372.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.5 %

12

Type of Reporting Person (See Instructions)

IA

Comment for Type of Reporting Person: The calculation is based upon 1,161,372 shares of Common Stock beneficially owned as of 08/06/2026 and a total of 21,203,552 shares of Common Stock, $0.001 par value per share, outstanding as of May 28, 2026, as reported by the Issuer in its Definitive Proxy Statement on Schedule 14A filed with the Securities and Exchange Commission on June 12, 2026.

SCHEDULE 13G

CUSIP Number(s): 714157203

1

Names of Reporting Persons

Kaufman Michael A

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 1,161,372.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 1,161,372.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

1,161,372.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.5 %

12

Type of Reporting Person (See Instructions)

IN

Comment for Type of Reporting Person: The calculation is based upon 1,161,372 shares of Common Stock beneficially owned as of 08/06/2026 and a total of 21,203,552 shares of Common Stock, $0.001 par value per share, outstanding as of May 28, 2026, as reported by the Issuer in its Definitive Proxy Statement on Schedule 14A filed with the Securities and Exchange Commission on June 12, 2026.

SCHEDULE 13G

Item 1.
(a)	Name of issuer: PERMA FIX ENVIRONMENTAL SERVICES INC
(b)	Address of issuer's principal executive offices: 8302 DUNWOODY PLACE, SUITE 250, ATLANTA, GEORGIA, 30350.
Item 2.
(a)	Name of person filing: This Schedule 13G is being filed by: i. MAK Capital Fund LP ("MAK Fund") ii. MAK Capital One L.L.C. ("MAK Capital"); and iii. Michael A. Kaufman ("Mr. Kaufman," and collectively with MAK Fund and MAK Capital, the "Reporting Persons")
(b)	Address or principal business office or, if none, residence: The principal business address of (i) MAK Fund is c/o Wakefield Quin, Victoria Place, 31 Victoria Street, Bermuda; and (ii) MAK Capital and Mr. Kaufman is 590 Madison Avenue, 31st Floor, New York, NY 10022.
(c)	Citizenship: MAK Capital Fund LP is a Bermuda limited partnership. MAK Capital One L.L.C. is a Delaware limited liability company. Mr. Kaufman is a United States citizen.
(d)	Title of class of securities: Common Stock, $0.001 par value per share
(e)	CUSIP Number(s): 714157203
Item 3.	If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:
(k)	Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.	Ownership
(a)	Amount beneficially owned: 1,161,372
(b)	Percent of class: 5.5% The calculation is based upon 1,161,372 shares of Common Stock beneficially owned as of 08/06/2026 and a total of 21,203,552 shares of Common Stock, $0.001 par value per share, outstanding as of May 28, 2026, as reported by the Issuer in its Definitive Proxy Statement on Schedule 14A filed with the Securities and Exchange Commission on June 12, 2026.
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 0
	(ii) Shared power to vote or to direct the vote: 1,161,372
	(iii) Sole power to dispose or to direct the disposition of: 0
	(iv) Shared power to dispose or to direct the disposition of: 1,161,372
Item 5.	Ownership of 5 Percent or Less of a Class.
	Not Applicable
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	Not Applicable
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	Not Applicable
Item 8.	Identification and Classification of Members of the Group.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

MAK Capital Fund LP

Signature:	/s/ Michael A. Kaufman
Name/Title:	Managing Member
Date:	08/06/2026

MAK CAPITAL ONE LLC

Signature:	/s/ Michael A. Kaufman
Name/Title:	Managing Member
Date:	08/06/2026

Kaufman Michael A

Signature:	/s/ Michael A. Kaufman
Name/Title:	Michael A. Kaufman
Date:	08/06/2026