Addex Therapeutics 13D/A: Timothy Dyer Holds 18.2 M Shares (12.9%)

Rhea-AI Filing Summary

Schedule 13D/A (Amendment 8) – Addex Therapeutics Ltd (ADXN)

The filing, triggered on 20 June 2025, discloses the current beneficial ownership position of Chief Executive Officer Timothy Mark Dyer in Addex Therapeutics Ltd. Dyer reports ownership or control over 18,208,437 ordinary shares, equal to 12.94 % of the company’s 139,391,883 outstanding ordinary shares as last reported in the Form 6-K filed on 20 June 2025.

Key ownership figures:

• Sole voting and dispositive power: 18,208,437 shares
• Shared voting/dispositive power: 0 shares
• Breakdown: 16,848,979 ordinary shares held outright and 1,359,458 shares issuable upon exercise of options that are exercisable within 60 days of 20 June 2025.

The filing details the history of share acquisitions and option grants from 2007 through 2025, including purchases with personal funds in various private placements (e.g., 36,364 shares at CHF 2.75 on 9 Aug 2013) and numerous option grants that were largely exercised on 26 Oct 2022 at a deferred strike price of CHF 0.13 per share. Dyer has also regularly received ordinary-share compensation in his capacity as CEO.

No criminal or civil proceedings are disclosed against the reporting person, and the source of funds for all cash purchases was personal funds (“PF, OO”). The filing reports citizenship in both Switzerland and the United Kingdom.

For investors, the amendment confirms that the company’s chief executive maintains a double-digit equity stake, signalling strong insider alignment but does not indicate any new purchase or sale since the prior amendment. No additional financing, earnings, or strategic transactions are discussed in this document.

Positive

• Significant insider alignment: CEO Timothy Dyer controls 12.94 % of outstanding shares, indicating vested interest in shareholder value.

Negative

• None.

Insights

Financial Analyst

TL;DR: CEO still controls 12.9 % of ADXN; no buying/selling, just updated disclosure—neutral but shows insider alignment.

The amendment merely updates Timothy Dyer’s beneficial ownership. His 18.2 million-share stake, including 1.36 million vested options, equals 12.94 % of the float. That figure is broadly stable with prior filings, so there is no incremental change in control risk. From a valuation lens, significant insider ownership is commonly viewed as positive for alignment, yet without fresh purchases the document is informational rather than catalytic. Liquidity impact is negligible, and no financing or strategic intent is implied.

Corporate Governance Expert

TL;DR: Filing confirms CEO’s sizeable stake; reinforces governance alignment, no material governance red flags.

With sole voting power over 12.94 % of shares, Dyer remains a key influence in shareholder decisions but falls short of blocking minority protections. The absence of group membership boxes and shared power lines indicates he acts individually, limiting concerns of concert-party arrangements. Clean legal history disclosures reduce governance risk. Overall, the amendment maintains transparency rather than signalling a shift in governance structure.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 8)

Addex Therapeutics Ltd.

(Name of Issuer)

American Depositary Shares, each representing 120 ordinary shares Ordinary shares

(Title of Class of Securities)

00654J206

(CUSIP Number)

Timothy Mark Dyer
c/o Addex Therapeutics Ltd, Chemin des Mines 9
Geneva, V8, CH-1202
41 22 884 1555

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

06/20/2025

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.

The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D

CUSIP No. 00654J206

1

Name of reporting person

Timothy Mark Dyer

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

PF, OO

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

SWITZERLAND

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 18,208,437.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 18,208,437.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

18,208,437.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

12.94 %

14

Type of Reporting Person (See Instructions)

IN

Comment for Type of Reporting Person:

(1) Consists of 16,848,979 ordinary shares and 1,359,458 shares issuable upon exercise of options exercisable within 60 days of June 20, 2025. (2) Represents the percentage ownership based on 139,391,883 ordinary shares of Addex Therapeutics Ltd outstanding asof June 18, 2025, as reported in the latest quarterly report on form 6K (file No.001-39179) filed on June 20, 2025.

SCHEDULE 13D

Item 1.	Security and Issuer
(a)	Title of Class of Securities: American Depositary Shares, each representing 120 ordinary shares Ordinary shares
(b)	Name of Issuer: Addex Therapeutics Ltd.
(c)	Address of Issuer's Principal Executive Offices: Chemin des Mines 9, Geneva, SWITZERLAND , CH-1202.
Item 1 Comment: This Schedule 13D relates to the ordinary shares, nominal value CHF 0.01 per share (the "Shares"), of Addex Therapeutics Ltd (the "Issuer"). The Issuer's principal executive office is located at Chemin des Mines 9, CH- 1202 Geneva, Switzerland.
Item 2.	Identity and Background
(a)	Timothy Mark Dyer, an individual ("Reporting Person").
(b)	The business address of Reporting Person is c/o Addex Therapeutics Ltd, Chemin des Mines 9, CH- 1202 Geneva, Switzerland.
(c)	Reporting Person is the Chief Executive Officer and a member of the Board of Directors of the Issuer.
(d)	During the last five years, Reporting Person has not been (1) convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors) or (2) a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding has been or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.
(e)	During the last five years, Reporting Person has not been (1) convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors) or (2) a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding has been or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.
(f)	Reporting Person is a citizen of Switzerland and United Kingdom.
Item 3.	Source and Amount of Funds or Other Consideration
	Reporting Person is deemed to beneficially own 18,208,437 Shares of the Issuer as reflected in this Schedule 13D. Prior to May 21, 2007, Reporting Person acquired 7,811 founder shares at a purchase price of CHF 1.00. The source of funds for such purchase was Reporting Person's personal funds. On August 9, 2013, Reporting Person acquired 36,364 Shares at a purchase price of CHF 2.75 per share through participation in a private placement. The source of funds for such purchase was Reporting Person's personal funds. On June 30, 2014, Reporting Person was granted stock options from the Issuer to purchase 400,000 Shares issuable upon exercise of options as compensation for his service as Chief Executive Officer of the Issuer. On October 26, 2022, Reporting Person exercised the options and acquired 400,000 Shares that are all freely tradable. The deferred strike price was CHF 0.13 for each share acquired. On July 1, 2014, Reporting Person received 18,143 Shares as compensation for his service as Chief Executive Officer of the Issuer. On July 14, 2014, Reporting Person received 24,588 Shares as compensation for his service as Chief Executive Officer of the Issuer. On January 7, 2015, Reporting Person received 17,063 Shares as compensation for his service as Chief Executive Officer of the Issuer. On March 6, 2015, Reporting Person acquired 33,333 Shares at a purchase price of CHF 3.00 per share during a private placement. The source of funds for such purchase was Reporting Person's personal funds. On July 28, 2015, Reporting Person received 17,149 Shares as compensation for his service as Chief Executive Officer of the Issuer. On January 28, 2016, Reporting Person received 17,461 Shares as compensation for his service as Chief Executive Officer of the Issuer. On August 2, 2016, Reporting Person received 20,263 Shares as compensation for his service as Chief Executive Officer of the Issuer. On January 16, 2017, Reporting Person received 23,001 Shares as compensation for his service as Chief Executive Officer of the Issuer. On February 28, 2017, Reporting Person was granted stock options from the Issuer to purchase 229,480 Shares issuable upon exercise of options as compensation for his service as Chief Executive Officer of the Issuer. On October 26, 2022, Reporting Person exercised the options and acquired 229,480 Shares that are all freely tradable. The deferred strike price was CHF 0.13 for each share acquired. On July 28, 2017, Reporting Person received 23,187 Shares as compensation for his service as Chief Executive Officer of the Issuer. On December 23, 2017, Reporting Person was granted stock options from the Issuer to purchase 1,052,250 Shares. On October 26, 2022, Reporting Person exercised the options and acquired 1,052,250 Shares that are all freely tradable. The deferred strike price was CHF 0.13 for each share acquired. On December 23, 2017, Reporting Person acquired 108,000 Shares through the exercise of options of which 53,000 and 55,000 were received on June 1, 2010 and November 15, 2011 respectively. The exercise price was CHF 1.00 for the Shares acquired and the source of funds for such purchase was Reporting Person's personal funds. On January 4, 2018, Reporting Person received 24,519 Shares as compensation for his service as Chief Executive Officer of the Issuer. On August 15, 2018, Reporting Person received 18,226 Shares as compensation for his service as Chief Executive Officer of the Issuer. On March 28, 2018, Reporting Person acquired 31,948 Shares at a purchase price of CHF 3.13 per share through participation in a private placement. The source of funds for such purchase was Reporting Person's personal funds. On June 1, 2018, Reporting Person was granted stock options from the Issuer to purchase 1,199,662 Shares. On October 26, 2022, Reporting Person exercised the options and acquired 1,199,662 Shares that are all freely tradable. The deferred strike price was CHF 0.13 for each share acquired. On January 1, 2019, Reporting Person was granted stock options from the Issuer to purchase 243,506 Shares. On October 26, 2022, Reporting Person exercised the options and acquired 243,506 Shares that are all freely tradable. The deferred strike price was CHF 0.13 for each share acquired. On January 4, 2019, Reporting Person received 14,136 Shares as compensation for his service as Chief Executive Officer of the Issuer. On April 1, 2020, Reporting Person was granted stock options from the Issuer to purchase 698,011. On October 26, 2022, Reporting Person exercised the options and acquired 698,011 Shares that are all freely tradable. The deferred strike price was CHF 0.13 for each Share acquired. On May 17, 2021, Reporting Person was granted stock options from the Issuer to purchase 700,000 Shares. On October 26, 2022, Reporting Person exercised the options and acquired 700,000 Shares that are all freely tradable. The deferred strike price was CHF 0.13 for each share acquired. On April 12, 2022, Reporting Person was granted stock options from the Issuer to purchase 2,051,972 Shares. On October 26, 2022, Reporting Person exercised the options and acquired 2,051,972 shares. Of these Shares 341,995 are not freely tradable as of June 20, 2025. The deferred strike price was CHF 0.13 for each share acquired. On October 5, 2022, Reporting Person was granted stock options from the Issuer to purchase 2,830,873 Shares. On October 26, 2022, Reporting Person exercised the options and acquired 2,830,873 Shares. Of these shares 825,671 are not freely tradable as of June 20, 2025. The deferred strike price was CHF 0.13 for each share acquired. On May 12, 2023, Reporting Person was granted stock options from the Issuer to purchase 7,008,033 Shares. On November 27, 2023, Reporting Person exercised the options and acquired 7,008,033 Shares. Of these shares 3,066,014 are not freely tradable as of June 20, 2025. The deferred strike price was CHF 0.043 for each share acquired. On January 8, 2024, Reporting Person was granted a stock option from the Issuer to purchase 3,369,796 shares at an exercise price of CHF 0.05. The shares underlying this option vest in 48 equal monthly installments, subject to Timothy Mark Dyer's continuous service as Chief Executive Officer of the issuer. As of June 20, 2025, 1,359,458 Shares are issuable upon exercise of options as compensation for his service as Chief Executive Officer of the Issuer. Unless specifically stated above, Reporting Person paid no compensation for the Shares.
Item 4.	Purpose of Transaction
	The Reporting Person acquired the securities of the Issuer at founding, through the exercise of options, acquisitions through participation in private placements and in consideration for his services as Chief Executive Officer of the Issuer. The reporting person also received shares issuable upon exercise of options. The terms of the Reporting Person's employment arrangements for 2024 were set forth in the Issuer's Annual Report on Form 20-F for such period filed by the Issuer with the Securities and Exchange Commission on May 15, 2025. Except in respect of such employment arrangements as set forth therein, the Reporting Person does not have any present plans which relate to or would result in: However, the Reporting Person reserves the right to change its plans at any time, as it deems appropriate, in light of its ongoing evaluation of (i) its business and liquidity objectives; (ii) the Issuer's financial condition, business, operations, competitive position, prospects and/or Share price; (iii) industry, economic and/or securities markets conditions; (iv) alternative investment opportunities; and (v) other relevant factors.
Item 5.	Interest in Securities of the Issuer
(a)	As of the date hereof, Reporting Person beneficially owns 18,208,437 Shares, which represents approximately 12.94% of the Issuer's Shares, consisting of (i) 16,848,979 Shares (ii) 1,359,458 Shares issuable upon exercise of options exercisable within 60 days of June 20, 2025.
(b)	Reporting Person may be deemed to hold sole voting and dispositive power over his 18,208,437 Shares of the Issuer.
(c)	Other than the acquisition of the shares as reported herein, and as described under Item 4, Reporting Person has not effected any transactions in the shares of the Issuer during the past 60 days or since the most recent filing of Schedule 13D, whichever is less.
(d)	To the best knowledge of Reporting Person, no person other than the Reporting Person has the right to receive, or the power to direct the receipt of, dividends from, or the proceeds from the sale of the 18,208,437 Shares reported in Item 5(a).
(e)	Not applicable.
Item 6.	Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer
	The information furnished in Item 3 is incorporated into this Item 6 by reference.
Item 7.	Material to be Filed as Exhibits.
	Not applicable.

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.

Timothy Mark Dyer

Signature:	/s/ Timothy Mark Dyer
Name/Title:	Timothy Mark Dyer
Date:	06/23/2025

FAQ

How many Addex Therapeutics (ADXN) shares does CEO Timothy Dyer currently control?

He reports beneficial ownership of 18,208,437 ordinary shares.

What percentage of ADXN’s outstanding shares does this represent?

The stake equals 12.94 % of the 139,391,883 shares outstanding as of 18 June 2025.

Does the Schedule 13D/A show any recent purchases or sales by the CEO?

No. The amendment updates existing holdings; it does not disclose new acquisitions or dispositions after 26 Oct 2022.

Are any of the reported shares subject to options?

Yes. 1,359,458 shares are issuable upon exercise of options that are exercisable within 60 days of 20 June 2025.

Does the filing mention any legal proceedings involving the reporting person?

No. The filing states the CEO has no criminal or civil proceedings relevant to securities laws in the past five years.