Thalassa Investment SC 13G/A Beneficial ownership report (amended)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

SCHEDULE 13G/A

Under the Securities Exchange Act of 1934

(Amendment No. 1)*

Castor Maritime Inc.

(Name of Issuer)

Common Stock, $0.001 Par Value Per Share

(Title of Class of Securities)

Y1146L109

(CUSIP Number)

December 31, 2019

(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)

[X] Rule 13d-1(d)

__________

*The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in 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).

CUSIP No.

Y1146L109

1.	NAME OF REPORTING PERSONS
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)


	Thalassa Investment Co. S.A.


2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
		(a) [_]
		(b) [X]


3.	SEC USE ONLY




4.	CITIZENSHIP OR PLACE OF ORGANIZATION


	The Republic of Liberia


NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

5.	SOLE VOTING POWER


	0


6.	SHARED VOTING POWER


	1,124,094*


7.	SOLE DISPOSITIVE POWER


	0


8.	SHARED DISPOSITIVE POWER


	1,124,094


9.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON


	1,124,094


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)


	33.88%**


12.	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) CO

* Thalassa Investment Co. S.A. also owns 12,000 Series B Preferred Shares. Each Series B Preferred Share has the voting power of 100,000 common shares.

**Based on 3,318,112 common shares of the Issuer, par value $0.001 per share, (the “Shares”) issued and outstanding.

CUSIP No.

Y1146L109

1.	NAME OF REPORTING PERSONS
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)


	Petros Panagiotidis


2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
		(a) [_]
		(b) [X]


3.	SEC USE ONLY




4.	CITIZENSHIP OR PLACE OF ORGANIZATION


	Greece


NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

5.	SOLE VOTING POWER


	0


6.	SHARED VOTING POWER


	1,124,094*


7.	SOLE DISPOSITIVE POWER


	0


8.	SHARED DISPOSITIVE POWER


	1,124,094


9.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON


	1,124,094


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)


	33.88%**


12.	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) IN

* Mr. Panagiotidis is the sole shareholder of Thalassa and he disclaims beneficial ownership of the 1,124,094 common shares except to the extent of his pecuniary, voting and dispositive interests in such common shares. Thalassa Investment Co. S.A. also owns 12,000 Series B Preferred Shares. Each Series B Preferred Share has the voting power of 100,000 common shares.

**Based on 3,318,112 common shares of the Issuer, par value $0.001 per share, (the “Shares”) issued and outstanding.

CUSIP No.

Y1146L109

Item 1.	(a).	Name of Issuer:

		Castor Maritime Inc.

	(b).	Address of issuer’s principal executive offices:

		223 Christodoulou Chatzipavlou Street, Hawaii Royal Gardens, 3036 Limassol, Cyprus

Item 2.	(a).	Name of person filing: Petros Panagiotidis and Thalassa Investment Co. S.A.

	(b).	Address of Principal Business Office or, if none, Residence:
		Thalassa Investment Co. S.A.
		223 Christodoulou Chatzipavlou Street, Hawaii Royal Gardens, 3036 Limassol, Cyprus

	(c).	Citizenship:

		Petros Panagiotidis is a citizen of Greece. Thalassa Investment Co. S.A. (“Thalassa”) is organized under the laws of Liberia.

	(d).	Title of class of securities:

		Common Stock, $0.001 par value per share

	(e).	CUSIP No.:

		Y1146L109

Item 3.

If This Statement is filed pursuant to §§.240.13d-1(b) or 240.13d-2(b), or (c);

Not applicable.

Item 4.

Ownership.

Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.

	(a)(b)	Amount beneficially owned and percent of Class:
		Thalassa Investment Co. S.A. (“Thalassa”) is the beneficial owner of 1,124,094 Shares, which constitutes approximately 33.88% of the total number of Shares outstanding. Petros Panagiotidis is the sole shareholder of Thalassa. Mr. Panagiotidis disclaims beneficial ownership of the 1,124,094 common shares except to the extent of his pecuniary, voting and dispositive interests in such common shares.

(c)	Number of shares as to which the Reporting Persons have:

	(i)	Sole power to vote or to direct the vote: 0

	(ii)	Shared power to vote or to direct the vote: 1,124,094

	(iii)	Sole power to dispose or to direct the disposition of: 0

	(iv)	Shared power to dispose or to direct the disposition of: 1,124,094

Item 5.

Ownership of Five Percent or Less of a Class.

	If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following: [_].
	This Item 5 is not applicable.

Item 6.

Ownership of More Than Five Percent on Behalf of Another Person.

If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than five percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required.

This Item 6 is 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.

	If a parent holding company or Control person has filed this schedule, pursuant to Rule 13d-1(b)(1)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating the identity and the Item 3 classification of the relevant subsidiary. If a parent holding company or control person has filed this schedule pursuant to Rule 13d-1(c) or Rule 13d-1(d), attach an exhibit stating the identification of the relevant subsidiary. This Item 7 is not applicable.

Item 8.	Identification and Classification of Members of the Group.

	If a group has filed this schedule pursuant to ss.240.13d-1(b)(1)(ii)(J), so indicate under Item 3(j) and attach an exhibit stating the identity and Item 3 classification of each member of the group. If a group has filed this schedule pursuant to ss.240.13d-1(c) or ss.240.13d-1(d), attach an exhibit stating the identity of each member of the group. This Item 8 is not applicable.

Item 9.	Notice of Dissolution of Group.

	Notice of dissolution of a group may be furnished as an exhibit stating the date of the dissolution and that all further filings with respect to transactions in the security reported on will be filed, if required, by members of the group, in their individual capacity. See Item 5. This Item 9 is not applicable.

Item 10.	Certification.

	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 such purpose or effect.

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.

February 6, 2020

	(Date)

	THALASSA INVESTMENT CO. S.A.

	By:	/s/ Loucas Hadjiyiangou
	Name:	Loucas Hadjiyiangou
	Title:	Director
	PETROS PANAGIOTIDIS*
	By:	/s/ Petros Panagiotidis

*	The Reporting Persons disclaim beneficial ownership except to the extent of their pecuniary, voting and dispositive interests therein.

JOINT FILING UNDERTAKING

The undersigned, being duly authorized thereunto, hereby execute this agreement as an exhibit to this Schedule 13G/A with respect to the shares of common stock of Castor Maritime Inc. to evidence the agreement of the below-named parties, in accordance with the rules promulgated pursuant to the Securities Exchange Act of 1934, as amended, to file this Schedule 13G/A, and any amendments hereto, jointly on behalf of each such party.

	February 6, 2020
	(Date)

	THALASSA INVESTMENT CO. S.A.

	By:	/s/ Loucas Hadjiyiangou
	Name:	Loucas Hadjiyiangou
	Title:	Director
	PETROS PANAGIOTIDIS
	By:	/s/ Petros Panagiotidis

Thalassa Investment SC 13G/ABeneficial ownership report (amended)