MARA CEO sells 27,505 shares under 10b5-1 plan

MARA Holdings, Inc. Chief Executive Officer Frederick G. Thiel reported two Form 4 transactions in the company’s common stock dated May 18, 2026.

Rhea-AI Filing Summary

MARA Holdings, Inc. Chief Executive Officer Frederick G. Thiel reported two Form 4 transactions in the company’s common stock dated May 18, 2026. He executed an open-market sale of 27,505 shares at $12.00 per share. In a separate transaction, 27,316 shares were withheld to cover his tax obligations arising from vesting of restricted stock units, which was not an open-market sale. The filing notes that the sale was carried out under a pre-arranged Rule 10b5-1 trading plan, indicating it was scheduled in advance rather than being a discretionary trade.

Insider Trade Summary 10b5-1

Net Seller: 27,505 shares

Net Sell 2 txns

Insider Thiel Frederick G

Role Chief Executive Officer

Sold 27,505 shs ($330K)

Type	Security	Shares	Price	Value
Exercise Price or Tax Liability	Common Stock	27,316	$11.46	$313K
Sale	Common Stock	27,505	$12.00	$330K

Holdings After Transaction: Common Stock — 4,589,514 shares (Direct)

Footnotes (2)

1. F1. Reflects shares of the issuer's common stock withheld to cover the reporting person's tax liability in connection with the vesting of restricted stock units. This transaction was not an open market sale by the reporting person.
2. F2. The sale reported in this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on May 28, 2025.

Key Figures

Open-market sale shares: 27,505 shares Sale price: $12.00/share Shares withheld for taxes: 27,316 shares +2 more

5 metrics

Open-market sale shares 27,505 shares Common Stock sold on May 18, 2026

Sale price $12.00/share Price for 27,505 Common Stock shares sold

Shares withheld for taxes 27,316 shares Withheld to cover tax liability on RSU vesting

Tax withholding reference price $11.46/share Value used for 27,316-share tax-withholding disposition

Net open-market effect 27,505 shares sold NetBuySellShares from transaction summary

Key Terms

Rule 10b5-1 trading plan, restricted stock units, tax-withholding disposition, open-market sale

4 terms

Rule 10b5-1 trading plan regulatory

"The sale reported in this Form 4 was effected pursuant to a Rule 10b5-1 trading plan"

A Rule 10b5-1 trading plan is a pre-arranged schedule that allows company insiders to buy or sell stock at specific times, even if they have inside information. It helps prevent accusations of unfair trading by making these transactions look planned and transparent, rather than sneaky or illegal.

restricted stock units financial

"tax liability in connection with the vesting of restricted stock units"

Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.

tax-withholding disposition financial

"transaction_action: "tax-withholding disposition" for 27,316.0000 shares"

A tax-withholding disposition is an event or transaction—such as selling or transferring securities, exercising options, or receiving compensation—that triggers a requirement to hold back part of the payment and remit it to tax authorities. It matters to investors because it reduces the cash they receive immediately and can change the timing and amount of taxable income, like a cashier taking a portion of your sale proceeds to pay taxes before you get the rest.

open-market sale financial

"transaction_action: "open-market sale" for 27,505.0000 shares at $12.0000"

An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.

FAQ

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

What did MARA CEO Frederick Thiel report in this Form 4 filing for MARA?

Frederick Thiel reported an open-market sale of 27,505 MARA common shares at $12.00 on May 18, 2026. He also reported 27,316 shares withheld to cover taxes from restricted stock unit vesting, which was not an open-market sale.

At what price did MARA CEO Frederick Thiel sell shares in this Form 4?

He sold 27,505 shares of MARA common stock at $12.00 per share. This sale was reported as an open-market transaction and was executed pursuant to a pre-established Rule 10b5-1 trading plan adopted earlier.

Were all MARA shares in this Form 4 sold on the open market?

No. While 27,505 shares were sold in an open-market transaction, another 27,316 shares were withheld solely to cover Frederick Thiel’s tax liability from restricted stock unit vesting and are specifically described as not an open-market sale.

What is the significance of the Rule 10b5-1 trading plan in MARA’s Form 4?

The filing states the sale was made under a Rule 10b5-1 trading plan adopted by Frederick Thiel. Such plans pre-schedule trades, indicating the timing of this 27,505-share sale was set in advance rather than chosen opportunistically.

How many MARA shares were withheld for taxes in this Form 4 transaction?

The Form 4 shows 27,316 shares of MARA common stock were withheld to satisfy Frederick Thiel’s tax obligations from restricted stock unit vesting. The filing clarifies this tax-withholding disposition was not an open-market sale transaction.

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

Form 4 Insider Transactions: What Each Field Means →

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

Add on Google Not now

Accepted by SEC EDGAR 05/20/2026 - 07:00 PM EDT Learn about SEC filing dates

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Thiel Frederick G

(Last) (First) (Middle)

C/O MARA HOLDINGS, INC.

1010 SOUTH FEDERAL HIGHWAY, SUITE 2700

(Street)

HALLANDALE BEACH FLORIDA 33009

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
MARA Holdings, Inc. [ MARA ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Executive Officer

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/18/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	05/18/2026		F		27,316(1)	D	$11.46	4,617,019	D
Common Stock	05/18/2026		S(2)		27,505	D	$12	4,589,514	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Reflects shares of the issuer's common stock withheld to cover the reporting person's tax liability in connection with the vesting of restricted stock units. This transaction was not an open market sale by the reporting person.

2. The sale reported in this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on May 28, 2025.

	/s/ Zabi Nowaid, Attorney-in-Fact for Fred Thiel	05/20/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)