Initial Statement of Beneficial Ownership (3)

FORM 3	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES	OMB APPROVAL OMB Number: 3235-0104 Estimated average burden hours per response... 0.5
	Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

1. Name and Address of Reporting Person ^*

Bruckner Scott

2. Date of Event Requiring Statement (MM/DD/YYYY) 2/1/2020

3. Issuer Name and Ticker or Trading Symbol

Casa Systems Inc [CASA]

(Last) (First) (Middle)

C/O CASA SYSTEMS, INC., 100 OLD RIVER ROAD

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

_____ Director _____ 10% Owner
___X___ Officer (give title below) _____ Other (specify below)
Interim CFO /

(Street)

ANDOVER, MA 01810

(City) (State) (Zip)

5. If Amendment, Date Original Filed(MM/DD/YYYY)

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)
Common Stock	8308	D

*Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)*
1. Title of Derivate Security (Instr. 4)	2. Date Exercisable and Expiration Date (MM/DD/YYYY)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
1. Title of Derivate Security (Instr. 4)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	4. Conversion or Exercise Price of Derivative Security		6. Nature of Indirect Beneficial Ownership (Instr. 5)
Stock Option (Right to Buy)	⁽¹⁾	12/13/2027	Common Stock	375000	$13.00	D
Restricted Stock Units ⁽²⁾	⁽³⁾	⁽³⁾	Common Stock	38169	$0.00	D

Explanation of Responses:
(1)	The option was granted on December 14, 2017 and vests over four years, with 25% of the original 375,000 shares underlying the option having vested on February 9, 2019, and 2.08333% of the original 375,000 shares vesting monthly thereafter.
(2)	Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, $0.001 par value per share (the "Common Stock") of Casa Systems, Inc. (the "Company") upon vesting, subject to the reporting person's continued service relationship with the Company and the other terms and conditions set forth in the applicable RSU agreement. In the sole discretion of the Company's board of directors, the Company may, with respect to any applicable vesting date, deliver to the reporting person Common Stock or cash having a fair market value equal to the number of shares of Common Stock underlying the portion of the RSU that vested on such date, payable within 30 days of the vesting date, less applicable taxes.
(3)	The RSUs are scheduled to vest over four years, with 25% of the 50,891 shares underlying the award having vested on January 1, 2020, and 25% of the shares underlying the award vesting at the end of each successive one-year period thereafter.

Remarks:
Exhibit 24.1 - Limited Power of Attorney for Section 16 Reporting Obligations

Reporting Owners
Reporting Owner Name / Address	Relationships
Reporting Owner Name / Address	Director	10% Owner	Officer	Other
Bruckner Scott C/O CASA SYSTEMS, INC. 100 OLD RIVER ROAD ANDOVER, MA 01810			Interim CFO

Signatures
/s/ Scott Bruckner		2/7/2020
^**Signature of Reporting Person		Date