SEC FORM 3

SEC FORM 3 SEC Form 3

FORM 3

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

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

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

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1. Name and Address of Reporting Person^*

van Hylckama Vlieg Johan

(Last)

(First)

(Middle)

C/O KALEIDO BIOSCIENCES, INC

(Street)

65 HAYDEN AVENUE

02421

(City)

(State)

(Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
05/05/2021

3. Issuer Name and Ticker or Trading Symbol
Kaleido Biosciences, Inc. [ KLDO ]

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

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

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

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

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

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
1. Title of Derivative Security (Instr. 4)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
Stock Option (Right to Buy)	⁽¹⁾	07/30/2029	Common Stock	125,000	7.67	D
Stock Option (Right to Buy)	⁽²⁾	11/14/2029	Common Stock	55,000	6.56	D
Stock Option (Right to Buy)	⁽³⁾	04/14/2030	Common Stock	40,000	6	D
Stock Option (Right to Buy)	⁽⁴⁾	10/14/2030	Common Stock	40,000	8.69	D
Stock Option (Right to Buy)	⁽⁵⁾	02/28/2031	Common Stock	40,000	9.81	D
Restricted Stock Units⁽⁶⁾	⁽⁷⁾	02/28/2022	Common Stock	6,707	0.00	D

Explanation of Responses:

1. 25% of this option vested on July 1, 2020 with the remainder vesting in 12 equal quarterly installments thereafter.

2. 25% of this option vested on November 15, 2020 with the remainder vesting in 12 equal quarterly installments thereafter.

3. 25% of this option vested on April 15, 2021 with the remainder vesting in 12 equal quarterly installments thereafter.

4. 25% of this option will vest on October 15, 2021 with the remainder vesting in 12 equal quarterly installments thereafter.

5. 25% of this option will vest on March 1, 2022 with the remainder vesting in 12 equal quarterly installments thereafter.

6. Each restricted stock unit represents a contingent right to receive one share of the Company's common stock.

7. The restricted stock units will vest 100% on February 28, 2022.

Remarks:

	/s/ Johan van Hylckama Vlieg	05/13/2021
	** 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 5 (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.