# EDGAR Filing Document

**Accession Number:** 0001144359
**File Stem:** 0001213900-23-008860
**Filing Date:** 2023-2
**Character Count:** 47367
**Document Hash:** 0885891797da8e896bdff6e4beb43e77
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001213900-23-008860.hdr.sgml**: 20230207

**ACCESSION NUMBER**: 0001213900-23-008860

**CONFORMED SUBMISSION TYPE**: SC 13G/A

**PUBLIC DOCUMENT COUNT**: 2

**FILED AS OF DATE**: 20230207

**DATE AS OF CHANGE**: 20230207

**GROUP MEMBERS**: JAMES L.L. TULLIS

**GROUP MEMBERS**: TULLIS DICKERSON PARTNERS III, L.L.C.

**GROUP MEMBERS**: TULLIS GROWTH FUND II, L.P.

**GROUP MEMBERS**: TULLIS GROWTH FUND, L.P.

**GROUP MEMBERS**: TULLIS-GROWTH PARTNERS II, L.L.C.

**GROUP MEMBERS**: TULLIS-GROWTH PARTNERS, L.L.C.

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** EXAGEN INC.
- **CENTRAL INDEX KEY:** 0001274737
- **STANDARD INDUSTRIAL CLASSIFICATION:** SERVICES-MEDICAL LABORATORIES [8071]
- **IRS NUMBER:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SC 13G/A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-91300
- **FILM NUMBER:** 23593790

**BUSINESS ADDRESS:**
- **STREET 1:** 1261 LIBERTY WAY
- **CITY:** VISTA
- **STATE:** CA
- **ZIP:** 92081
- **BUSINESS PHONE:** (760) 560-1501

**MAIL ADDRESS:**
- **STREET 1:** 1261 LIBERTY WAY
- **CITY:** VISTA
- **STATE:** CA
- **ZIP:** 92081

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** EXAGEN DIAGNOSTICS INC
- **DATE OF NAME CHANGE:** 20031230
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** TULLIS DICKERSON CAPITAL FOCUS III, L.P.
- **CENTRAL INDEX KEY:** 0001144359
- **IRS NUMBER:** 000000000

**FILING VALUES:**
- **FORM TYPE:** SC 13G/A

**BUSINESS ADDRESS:**
- **STREET 1:** ONE GREENWICH PLAZA
- **CITY:** GREENWICH
- **STATE:** CT
- **ZIP:** 06830
- **BUSINESS PHONE:** 2036298700

**MAIL ADDRESS:**
- **STREET 1:** ONE GREENWICH PLAZA
- **CITY:** GREENWICH
- **STATE:** CT
- **ZIP:** 06830

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** TULLIS DICKERSON CAPITAL FOCUS III LP
- **DATE OF NAME CHANGE:** 20010706

---

| |
|:---|
| **UNITED STATES** |
| **SECURITIES AND EXCHANGE COMMISSION** |
| **Washington, D.C. 20549** |

---

**SCHEDULE 13G**

Under the Securities Exchange Act of 1934<br> (Amendment No. 3)\*

**Exagen, Inc.**

(Name of Issuer)

Common shares, par value $0.001 per share

(Title of Class of Securities)

30068X103

(CUSIP Number)

December 31, 2022

(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)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;☒ 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 purposes 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: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 |
| (1) | NAMES OF REPORTING PERSONS<br>Tullis-Dickerson Capital Focus III, L.P. | NAMES OF REPORTING PERSONS<br>Tullis-Dickerson Capital Focus III, L.P. | NAMES OF REPORTING PERSONS<br>Tullis-Dickerson Capital Focus III, L.P. | NAMES OF REPORTING PERSONS<br>Tullis-Dickerson Capital Focus III, L.P. |
| (2) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) |
|  | (a) | (a) | ☐ | ☐ |
|  | (b) | (b) | ☐ | ☐ |
| (3) | SEC USE ONLY | SEC USE ONLY | SEC USE ONLY | SEC USE ONLY |
| (4) | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (5) | (5) | SOLE VOTING POWER<br>0  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (6) | (6) | SHARED VOTING POWER <br>1,112,357 (1) |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (7) | (7) | SOLE DISPOSITIVE POWER<br>0 |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (8) | (8) | SHARED DISPOSITIVE POWER <br>1,112,357 (1) |
| (9) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>1,112,357 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>1,112,357 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>1,112,357 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>1,112,357 (1) |
| (10) | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ |
| (11) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>6.82% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>6.82% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>6.82% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>6.82% (2) |
| (12) | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN |

---

(1) Represents 992,821 shares of Common Stock as
 well as 119,536 shares of Common Stock issuable upon exercise of Warrants held by Tullis-Dickerson
 Capital Focus III, L.P.

(2) Percentage calculated based
 on 16,319,488 shares of Common Stock outstanding as of November 18, 2022, as reported in
 the issuer's Quarterly Report on Form 10-Q for the quarter ended September 30, 2022.

---

| | | | | |
|:---|:---|:---|:---|:---|
| CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 |
| (1) | NAMES OF REPORTING PERSONS<br>Tullis Dickerson Partners III, L.L.C. | NAMES OF REPORTING PERSONS<br>Tullis Dickerson Partners III, L.L.C. | NAMES OF REPORTING PERSONS<br>Tullis Dickerson Partners III, L.L.C. | NAMES OF REPORTING PERSONS<br>Tullis Dickerson Partners III, L.L.C. |
| (2) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) |
|  | (a) | (a) | ☐ | ☐ |
|  | (b) | (b) | ☐ | ☐ |
| (3) | SEC USE ONLY | SEC USE ONLY | SEC USE ONLY | SEC USE ONLY |
| (4) | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (5) | (5) | SOLE VOTING POWER<br>0  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (6) | (6) | SHARED VOTING POWER <br>1,112,357 (1) |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (7) | (7) | SOLE DISPOSITIVE POWER<br>0 |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (8) | (8) | SHARED DISPOSITIVE POWER <br>1,112,357 (1) |
| (9) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>1,112,357 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>1,112,357 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>1,112,357 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>1,112,357 (1) |
| (10) | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ |
| (11) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>6.82% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>6.82% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>6.82% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>6.82% (2) |
| (12) | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN |

---

(1) Represents 992,821 shares of Common Stock as well as 119,536 shares of
 Common Stock issuable upon exercise of Warrants held by Tullis-Dickerson Capital Focus III,
 L.P. Tullis Dickerson Partners III, L.L.C. may be deemed to beneficially own these shares
 because the L.L.C. is a general partner of Tullis-Dickerson Capital Focus III, L.P.

(2) Percentage calculated based
 on 16,319,488 shares of Common Stock outstanding as of November 18, 2022, as reported in
 the issuer's Quarterly Report on Form 10-Q for the quarter ended September 30, 2022.

---

| | | | | |
|:---|:---|:---|:---|:---|
| CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 |
| (1) | NAMES OF REPORTING PERSONS<br>Tullis Growth Fund, L.P. | NAMES OF REPORTING PERSONS<br>Tullis Growth Fund, L.P. | NAMES OF REPORTING PERSONS<br>Tullis Growth Fund, L.P. | NAMES OF REPORTING PERSONS<br>Tullis Growth Fund, L.P. |
| (2) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) |
|  | (a) | (a) | ☐ | ☐ |
|  | (b) | (b) | ☐ | ☐ |
| (3) | SEC USE ONLY | SEC USE ONLY | SEC USE ONLY | SEC USE ONLY |
| (4) | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (5) | (5) | SOLE VOTING POWER<br>0  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (6) | (6) | SHARED VOTING POWER <br>587,843 (1) |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (7) | (7) | SOLE DISPOSITIVE POWER<br>0 |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (8) | (8) | SHARED DISPOSITIVE POWER <br>587,843 (1) |
| (9) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>587,843 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>587,843 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>587,843 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>587,843 (1) |
| (10) | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ |
| (11) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>3.60% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>3.60% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>3.60% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>3.60% (2) |
| (12) | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN |

---

(1) Represents 417,398 shares of Common Stock as well as 170,445 shares of
 Common Stock issuable upon exercise of Warrants held by Tullis Growth Fund, L.P.

(2) Percentage calculated based
 on 16,319,488 shares of Common Stock outstanding as of November 18, 2022, as reported in
 the issuer's Quarterly Report on Form 10-Q for the quarter ended September 30, 2022.

---

| | | | | |
|:---|:---|:---|:---|:---|
| CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 |
| (1) | NAMES OF REPORTING PERSONS<br>Tullis-Growth Partners, L.L.C. | NAMES OF REPORTING PERSONS<br>Tullis-Growth Partners, L.L.C. | NAMES OF REPORTING PERSONS<br>Tullis-Growth Partners, L.L.C. | NAMES OF REPORTING PERSONS<br>Tullis-Growth Partners, L.L.C. |
| (2) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) |
|  | (a) | (a) | ☐ | ☐ |
|  | (b) | (b) | ☐ | ☐ |
| (3) | SEC USE ONLY | SEC USE ONLY | SEC USE ONLY | SEC USE ONLY |
| (4) | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (5) | (5) | SOLE VOTING POWER<br>0  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (6) | (6) | SHARED VOTING POWER <br>587,843 (1) |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (7) | (7) | SOLE DISPOSITIVE POWER<br>0 |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (8) | (8) | SHARED DISPOSITIVE POWER <br>587,843 (1) |
| (9) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>587,843 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>587,843 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>587,843 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>587,843 (1) |
| (10) | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ |
| (11) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>3.60% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>3.60% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>3.60% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>3.60% (2) |
| (12) | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN |

---

(1) Represents 417,398 shares of Common Stock as well as 170,445 shares of
 Common Stock issuable upon exercise of Warrants held by Tullis Growth Fund, L.P. Tullis-Growth
 Partners, L.L.C. may be deemed to beneficially own these shares because the L.L.C. is a general
 partner of Tullis Growth Fund, L.P.

(2) Percentage calculated based
 on 16,319,488 shares of Common Stock outstanding as of November 18, 2022, as reported in
 the issuer's Quarterly Report on Form 10-Q for the quarter ended September 30, 2022.

---

| | | | | |
|:---|:---|:---|:---|:---|
| CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 |
| (1) | NAMES OF REPORTING PERSONS<br>Tullis Growth Fund II, L.P. | NAMES OF REPORTING PERSONS<br>Tullis Growth Fund II, L.P. | NAMES OF REPORTING PERSONS<br>Tullis Growth Fund II, L.P. | NAMES OF REPORTING PERSONS<br>Tullis Growth Fund II, L.P. |
| (2) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) |
|  | (a) | (a) | ☐ | ☐ |
|  | (b) | (b) | ☐ | ☐ |
| (3) | SEC USE ONLY | SEC USE ONLY | SEC USE ONLY | SEC USE ONLY |
| (4) | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (5) | (5) | SOLE VOTING POWER<br>0  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (6) | (6) | SHARED VOTING POWER <br>105,453 (1) |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (7) | (7) | SOLE DISPOSITIVE POWER<br>0 |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (8) | (8) | SHARED DISPOSITIVE POWER <br>105,453 (1) |
| (9) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>105,453 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>105,453 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>105,453 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>105,453 (1) |
| (10) | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ |
| (11) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>.65% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>.65% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>.65% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>.65% (2) |
| (12) | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN |

---

(1) Represents 105,453 shares of Common Stock held by Tullis Growth Fund
 II, L.P.

(2) Percentage calculated
 based on 16,319,488 shares of Common Stock outstanding as of November 18, 2022, as reported
 in the issuer's Quarterly Report on Form 10-Q for the quarter ended September 30, 2022.

---

| | | | | |
|:---|:---|:---|:---|:---|
| CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 |
| (1) | NAMES OF REPORTING PERSONS<br>Tullis-Growth Partners II, L.L.C. | NAMES OF REPORTING PERSONS<br>Tullis-Growth Partners II, L.L.C. | NAMES OF REPORTING PERSONS<br>Tullis-Growth Partners II, L.L.C. | NAMES OF REPORTING PERSONS<br>Tullis-Growth Partners II, L.L.C. |
| (2) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) |
|  | (a) | (a) | ☐ | ☐ |
|  | (b) | (b) | ☐ | ☐ |
| (3) | SEC USE ONLY | SEC USE ONLY | SEC USE ONLY | SEC USE ONLY |
| (4) | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>Delaware, United States of America |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (5) | (5) | SOLE VOTING POWER<br>0  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (6) | (6) | SHARED VOTING POWER <br>105,453 (1) |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (7) | (7) | SOLE DISPOSITIVE POWER<br>0 |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (8) | (8) | SHARED DISPOSITIVE POWER <br>105,453 (1) |
| (9) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>105,453 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>105,453 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>105,453 (1) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>105,453 (1) |
| (10) | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ |
| (11) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>.65% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>.65% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>.65% (2) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>.65% (2) |
| (12) | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>PN |

---

(1) Represents 105,453 shares of Common Stock held by Tullis Growth Fund
 II, L.P. Tullis-Growth Partners II, L.L.C. may be deemed to beneficially own these shares
 because the L.L.C. is a general partner of Tullis Growth Fund II, L.P.

(2) Percentage calculated
 based on 16,319,488 shares of Common Stock outstanding as of November 18, 2022, as reported
 in the issuer's Quarterly Report on Form 10-Q for the quarter ended September 30, 2022.

---

| | | | | |
|:---|:---|:---|:---|:---|
| CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 | CUSIP No: 30068X103 |
| (1) | NAMES OF REPORTING PERSONS<br>James L.L. Tullis | NAMES OF REPORTING PERSONS<br>James L.L. Tullis | NAMES OF REPORTING PERSONS<br>James L.L. Tullis | NAMES OF REPORTING PERSONS<br>James L.L. Tullis |
| (2) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) |
|  | (a) | (a) | ☐ | ☐ |
|  | (b) | (b) | ☐ | ☐ |
| (3) | SEC USE ONLY | SEC USE ONLY | SEC USE ONLY | SEC USE ONLY |
| (4) | CITIZENSHIP OR PLACE OF ORGANIZATION <br>United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>United States of America | CITIZENSHIP OR PLACE OF ORGANIZATION <br>United States of America |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (5) | (5) | SOLE VOTING POWER<br>52,296 (1)  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (6) | (6) | SHARED VOTING POWER <br>1,805,653 (2) |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (7) | (7) | SOLE DISPOSITIVE POWER<br>52,296 (1) |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH |  |  |  |
| NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | NUMBER OF<br> SHARES<br> BENEFICIALLY<br> OWNED BY<br> EACH<br> REPORTING<br> PERSON WITH | (8) | (8) | SHARED DISPOSITIVE POWER <br>1,805,653 (2) |
| (9) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>1,857,949 (3) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>1,857,949 (3) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>1,857,949 (3) | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON<br>1,857,949 (3) |
| (10) | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ☐ |
| (11) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>11.38% (4) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>11.38% (4) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>11.38% (4) | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)<br>11.38% (4) |
| (12) | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>IN, HC | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>IN, HC | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>IN, HC | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)<br>IN, HC |

---

(1) Represents 21,348 shares
 of Common Stock as well as 30,948 Options held by Mr. Tullis in his individual capacity.

(2) Represents 992,821 shares of Common Stock as well as 119,536 shares of
 Common Stock issuable upon exercise of Warrants held by Tullis-Dickerson Capital Focus III,
 L.P.; 417,398 shares of Common Stock as well as 170,445 shares of Common Stock issuable upon
 exercise of Warrants held by Tullis Growth Fund, L.P.; and 105,453 shares of Common Stock
 held by Tullis Growth Fund II, L.P. Mr. Tullis may be deemed to beneficially own all of these
 shares as principal of each of the foregoing entities.

(3) Represents
 992,821 shares of Common Stock as well as 119,536 shares of Common Stock issuable upon exercise
 of Warrants held by Tullis-Dickerson Capital Focus III, L.P.; 417,398 shares of Common Stock
 as well as 170,445 shares of Common Stock issuable upon exercise of Warrants held by Tullis
 Growth Fund, L.P.; 105,453 shares of Common Stock held by Tullis Growth Fund II, L.P.; and
 21,348 shares of Common Stock as well as 30,948 Options held by Mr. Tullis in his individual
 capacity. Mr. Tullis may be deemed to directly or beneficially own all of these shares as
 principal of each of the foregoing entities.

(4) Percentage calculated
 based on 16,319,488 shares of Common Stock outstanding as of November 18, 2022, as reported
 in the issuer's Quarterly Report on Form 10-Q for the quarter ended September 30, 2022.

**Item 1. Security and Issuer.**

&nbsp;&nbsp;&nbsp;&nbsp;**(a)** **Name of Issuer:** 

Exagen, Inc.

&nbsp;&nbsp;&nbsp;&nbsp;**(b)** **Address of Issuer:** 

1261 Liberty Way

Vista, CA 92081

**Item 2. Identity and Background.**

&nbsp;&nbsp;&nbsp;&nbsp;**(a)** **Name of Person Filing:** 

This statement is being filed on behalf of each of the following persons (each, a "Reporting Person" and collectively, the "Reporting Persons"):

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;i. Tullis-Dickerson Capital
 Focus III, L.P. ("  **<u>TD Capital Focus</u>** ")

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ii. Tullis-Dickerson Partners
 III, L.L.C., the general partner of TD Capital Focus

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;iii. Tullis Growth Fund,
 L.P. ("  **<u>Tullis Growth Fund</u>** ")

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;iv. Tullis-Growth Partners,
 L.L.C., the general partner of Tullis Growth Fund

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;v. Tullis Growth Fund
 II, L.P. ("  **<u>Tullis Growth Fund II</u>** ")

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;vi. Tullis-Growth Partners
 II, L.L.C., the general partner of Tullis Growth Fund II

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;vii. James
 L.L. Tullis as a principal of each of the foregoing entities and in his individual capacity

&nbsp;&nbsp;&nbsp;&nbsp;**(b)** **Address of Principal Business Office or, if none, Residence:** 

The address of the principal business office of each of the reporting persons is:

11770 US Highway One, Suite 503, Palm Beach Gardens, FL 33408

&nbsp;&nbsp;&nbsp;&nbsp;**(c)** **Citizenship or Place of Organization:** 

James L. L. Tullis is a citizen of the United States and each of the remaining Reporting Persons were formed in Delaware

&nbsp;&nbsp;&nbsp;&nbsp;**(d)** **Title of Class of Securities:** 

Common shares, par value $0.001 per share

&nbsp;&nbsp;&nbsp;&nbsp;**(e)** **CUSIP Number:** 

30068X103

**Item 3. If this statement is filed pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:**

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a) ☐ Broker
 or dealer registered under Section 15 of the Act (15 U.S.C. 78o).

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b) ☐ Bank
 as defined in Section 3(a)(6) of the Act (15 U.S.C. 78c).

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c) ☐ Insurance
 company as defined in Section 3(a)(19) of the Act (15 U.S.C. 78c).

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d) ☐ Investment
 company registered under Section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8).

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(e) ☐ An
 investment adviser in accordance with §240.13d-1(b)(1)(ii)(E);

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(f) ☐ An
 employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F);

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(g) ☐ A
 parent holding company or control person in accordance with §240.13d-1(b)(1)(ii)(G);

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(h) ☐ A
 savings association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C.
 1813);

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i) ☐ A
 church plan that is excluded from the definition of an investment company under Section 3(c)(14)
 of the Investment Company Act of 1940 (15 U.S.C. 80a-3);

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(j) ☐ A
 non-U.S. institution in accordance with §240.13d-1(b)(1)(ii)(J);

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(k) ☐ Group,
 in accordance with Rule 13d-1(b)(1)(ii)(K).

If filing as a non-U.S. institution in accordance with §240.13d-1(b)(1)(ii)(J), please specify the type of institution:

**Item 4. Ownership**

&nbsp;&nbsp;&nbsp;&nbsp;(a) **Amount Beneficially Owned:** 

See row 9 of the cover page of each Reporting Person.

As of December 31, 2022, the general partner of Tullis-Dickerson Capital Focus III, L.P., Tullis Dickerson Partners III, L.L.C. is deemed to beneficially own 1,112,357 shares of the Issuer's Common Stock. As the general partner of Tullis Growth Fund, L.P., Tullis-Growth Partners, L.L.C. is deemed to beneficially own 587,843 shares of the Issuer's Common Stock. As the general partner of Tullis Growth Fund II, L.P., Tullis-Growth Partners II, LLC is deemed to beneficially own 105,453 shares of the Issuer's Common Stock. James L.L. Tullis, in his individual capacity, beneficially owns 52,296 shares of the Issuer's Common Stock and is a principal of each of the foregoing entities and may be deemed to possess voting and investment control over, and may be deemed to have an indirect beneficial ownership with respect to the shares held by Tullis-Dickerson Capital Focus III, L.P., Tullis Growth Fund, L.P., and Tullis Growth Fund II, L.P.

Pursuant to Rule 13d-4 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), the Reporting Persons declare that filing this Schedule 13G shall not be construed as an admission that any such person is, for the purposes of Section 13(d) and/or Section 13(g) of the Exchange Act, the beneficial owner of any Common Stock covered by this Schedule 13G except to the extent of such person's direct ownership of such Common Stock, and except to the extent of such direct ownership, such beneficial ownership is expressly disclaimed by each Reporting Person.

&nbsp;&nbsp;&nbsp;&nbsp;(b) **Percent of Class:** 

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;i. Tullis-Dickerson Capital
 Focus III, L.P.: 6.82%

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ii. Tullis-Dickerson Partners
 III, L.L.C.: 6.82%

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;iii. Tullis Growth Fund,
 L.P.: 3.60%

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;iv. Tullis-Growth Partners,
 L.L.C.: 3.60%

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;v. Tullis Growth Fund II,
 L.P.: 0.65%

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;vi. Tullis-Growth Partners
 II, L.L.C., 0.65%

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;vii. James L. L. Tullis: 
 11.38% as a principal of each of the foregoing entities and 0.32%, individually

Percentage calculated based on 16,319,488 shares of Common Stock outstanding as of November 18, 2022, as reported in the issuer's Quarterly Report on Form 10-Q for the quarter ended September 30, 2022.

&nbsp;&nbsp;&nbsp;&nbsp;(c) Number of shares as to which such person has:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i) **Sole power to vote or to direct the vote:** 

See row 5 of the cover page of each Reporting Person.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii) **Shared power to vote or to direct the vote:** 

See row 6 of the cover page of each Reporting Person

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii) **Sole power to dispose or to direct the disposition of:** 

See row 7 of the cover page of each Reporting Person.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iv) **Shared power to dispose or to direct the disposition of:** 

See row 8 of the cover page of each Reporting Person.

**Item 5. Ownership of Five Percent or Less of a Class**

Not applicable.

**Item 6. Ownership of More than Five Percent on Behalf of Another Person** 

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.**

Not applicable.

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

Not applicable.

**Item 9. Notice of Dissolution of Group.**

Not applicable.

**Item 10. Certifications.**

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 that purpose or effect.

**SIGNATURES**

After reasonable inquiry and to the best of its knowledge and belief, the undersigned certifies that the information set forth in this statement is true, complete, and correct.

Dated: February 7, 2023

---

| | | |
|:---|:---|:---|
| **TULLIS-DICKERSON CAPITAL FOCUS III, L.P.** | **TULLIS-DICKERSON CAPITAL FOCUS III, L.P.** | **TULLIS-DICKERSON CAPITAL FOCUS III, L.P.** |
| **By:** | **Tullis-Dickerson Partners III, L.L.C., its general partner** | **Tullis-Dickerson Partners III, L.L.C., its general partner** |
| **By:** | /s/ James L.L. Tullis | /s/ James L.L. Tullis |
|  | **Name:** | **James L.L. Tullis** |
|  | **Title:** | **Manager** |
| **TULLIS GROWTH FUND, L.P.** | **TULLIS GROWTH FUND, L.P.** | **TULLIS GROWTH FUND, L.P.** |
| **By:** | **Tullis-Growth Partners, L.L.C., its general partner** | **Tullis-Growth Partners, L.L.C., its general partner** |
| **By:** | /s/ James L.L. Tullis | /s/ James L.L. Tullis |
|  | **Name:** | **James L.L. Tullis** |
|  | **Title:** | **Manager** |
| **TULLIS GROWTH FUND II, L.P.** | **TULLIS GROWTH FUND II, L.P.** | **TULLIS GROWTH FUND II, L.P.** |
| **By:** | **Tullis-Growth Partners II, L.L.C., its general partner** | **Tullis-Growth Partners II, L.L.C., its general partner** |
| **By:** | /s/ James L.L. Tullis | /s/ James L.L. Tullis |
|  | **Name:** | **James L.L. Tullis** |
|  | **Title:** | **Manager** |
| **TULLIS-DICKERSON PARTNERS III, L.L.C.** | **TULLIS-DICKERSON PARTNERS III, L.L.C.** | **TULLIS-DICKERSON PARTNERS III, L.L.C.** |
| **By:** | /s/ James L.L. Tullis | /s/ James L.L. Tullis |
|  | **Name:** | **James L.L. Tullis** |
|  | **Title:** | **Chief Executive Officer** |
| **TULLIS-GROWTH PARTNERS, L.L.C.** | **TULLIS-GROWTH PARTNERS, L.L.C.** | **TULLIS-GROWTH PARTNERS, L.L.C.** |
| **By:** | /s/ James L.L. Tullis | /s/ James L.L. Tullis |
|  | **Name:** | **James L.L. Tullis** |
|  | **Title:** | **Manager** |
| **TULLIS-GROWTH PARTNERS II, L.L.C.** | **TULLIS-GROWTH PARTNERS II, L.L.C.** | **TULLIS-GROWTH PARTNERS II, L.L.C.** |
| **By:** | /s/ James L.L. Tullis | /s/ James L.L. Tullis |
|  | **Name:** | **James L.L. Tullis** |
|  | **Title:** | **Chief Executive Officer** |
|  | /s/ James L.L. Tullis | /s/ James L.L. Tullis |
|  | **JAMES L.L. TULLIS**, **Individually** | **JAMES L.L. TULLIS**, **Individually** |

---

## Exhibit 99.1

**Exhibit 99.1**

JOINT FILING AGREEMENT PURSUANT TO RULE 13d-1(k)

The undersigned acknowledge and agree that the foregoing statement on Schedule 13G is filed on behalf of each of the undersigned and that all subsequent amendments to this statement on Schedule 13G shall be filed on behalf of each of the undersigned without the necessity of filing additional joint filing agreements. The undersigned acknowledge that each shall be responsible for the timely filing of such amendments, and for the completeness and accuracy of the information concerning him or it contained herein and therein, but shall not be responsible for the completeness and accuracy of the information concerning the others, except to the extent that he or it knows or has reason to believe that such information is inaccurate.

Dated February 7, 2023

---

| | | |
|:---|:---|:---|
| **TULLIS-DICKERSON CAPITAL FOCUS III, L.P.** | **TULLIS-DICKERSON CAPITAL FOCUS III, L.P.** | **TULLIS-DICKERSON CAPITAL FOCUS III, L.P.** |
| By: | Tullis-Dickerson Partners III, L.L.C., its general partner | Tullis-Dickerson Partners III, L.L.C., its general partner |
| By: | /s/ James L.L. Tullis | /s/ James L.L. Tullis |
|  | Name: | James L.L. Tullis |
|  | Title: | Manager |
| **TULLIS-DICKERSON PARTNERS III, L.L.C.** | **TULLIS-DICKERSON PARTNERS III, L.L.C.** | **TULLIS-DICKERSON PARTNERS III, L.L.C.** |
| By: | /s/ James L.L. Tullis | /s/ James L.L. Tullis |
|  | Name: | James L.L. Tullis |
|  | Title: | Manager |
| **TULLIS GROWTH FUND, L.P.** | **TULLIS GROWTH FUND, L.P.** | **TULLIS GROWTH FUND, L.P.** |
| By: | Tullis-Growth Partners, L.L.C., its general partner | Tullis-Growth Partners, L.L.C., its general partner |
| By: | /s/ James L.L. Tullis | /s/ James L.L. Tullis |
|  | Name: | James L.L. Tullis |
|  | Title: | Manager |
| **TULLIS-GROWTH PARTNERS, L.L.C.** | **TULLIS-GROWTH PARTNERS, L.L.C.** | **TULLIS-GROWTH PARTNERS, L.L.C.** |
| By: | /s/ James L.L. Tullis | /s/ James L.L. Tullis |
|  | Name: | James L.L. Tullis |
|  | Title: | Manager |

---

---

| | | |
|:---|:---|:---|
| **TULLIS GROWTH FUND II, L.P.** | **TULLIS GROWTH FUND II, L.P.** | **TULLIS GROWTH FUND II, L.P.** |
| By: | Tullis-Growth Partners II, L.L.C., its general partner | Tullis-Growth Partners II, L.L.C., its general partner |
| By: | /s/ James L.L. Tullis | /s/ James L.L. Tullis |
|  | Name: | James L.L. Tullis |
|  | Title: | Manager |
| **TULLIS-GROWTH PARTNERS II, L.L.C.** | **TULLIS-GROWTH PARTNERS II, L.L.C.** | **TULLIS-GROWTH PARTNERS II, L.L.C.** |
| By: | /s/ James L.L. Tullis | /s/ James L.L. Tullis |
|  | Name: | James L.L. Tullis |
|  | Title: | Chief Executive Officer |
| /s/ James L.L. Tullis | /s/ James L.L. Tullis | /s/ James L.L. Tullis |
| **JAMES L.L. TULLIS**, Individually | **JAMES L.L. TULLIS**, Individually | **JAMES L.L. TULLIS**, Individually |

---