Alector, Inc. — Major Shareholding Notification 2019

Feb 11, 2019

SC 13G 1 e618215_sc13g-alector.htm

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

SCHEDULE 13G

(Rule 13d-102)

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT

TO RULES 13d-1(b)(c), AND (d) AND AMENDMENTS THERETO FILED

PURSUANT TO RULE 13d-2(b)

(Amendment No. ) *

Alector, Inc.

(Name of Issuer)

Common Stock

(Title of Class of Securities)

014442107

(CUSIP Number)

February 11, 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)

☐ Rule 13d-1(d)

(Page 1 of 16 Pages)

---

• 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 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).

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CUSIP No. 014442107 13G Page 2 of 16

1.	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) Deerfield Mgmt, L.P.
2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*	(a)
☐ (b) ☒
3.	SEC USE ONLY
4.	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	5.	SOLE VOTING POWER 0
	6.	SHARED VOTING POWER 901,731 (1)
	7.	SOLE DISPOSITIVE POWER 0
	8.	SHARED DISPOSITIVE POWER 901,731 (1)
9.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 901,731 (1)
10.	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN
SHARES*	☐
11.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 1.32%
12.	TYPE OF REPORTING PERSON* PN

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(1) Comprised of shares of common stock held by Deerfield Special Situations Fund, L.P. and Deerfield Partners, L.P., of which Deerfield Mgmt, L.P. is the general partner.

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CUSIP No. 014442107 13G Page 3 of 16

1.	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) Deerfield Management Company, L.P.
2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*	(a)
☐ (b) ☒
3.	SEC USE ONLY
4.	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	5.	SOLE VOTING POWER 0
	6.	SHARED VOTING POWER 1,956,923 (2)
	7.	SOLE DISPOSITIVE POWER 0
	8.	SHARED DISPOSITIVE POWER 1,956,923 (2)
9.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,956,923 (2)
10.	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN
SHARES*	☐
11.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 2.86%
12.	TYPE OF REPORTING PERSON* PN

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(2) Comprised of shares of common stock held by Deerfield Special Situations Fund, L.P., Deerfield Partners, L.P., Deerfield Private Design Fund III, L.P. and Deerfield Private Design Fund IV, L.P., of which Deerfield Management Company, L.P. is the investment advisor.

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CUSIP No. 014442107 13G Page 4 of 16

| 1. | NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) Deerfield Mgmt
III, L.P. | |
| --- | --- | --- |
| 2. | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP | (a)
☐ (b) ☒ |
| 3. | SEC USE ONLY | |
| 4. | CITIZENSHIP OR PLACE OF ORGANIZATION Delaware | |
| NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH | 5. | SOLE VOTING POWER 0 |
| | 6. | SHARED VOTING POWER 527,596
(3) |
| | 7. | SOLE DISPOSITIVE POWER 0 |
| | 8. | SHARED DISPOSITIVE POWER 527,596 (3) |
| 9. | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 527,596 (3) | |
| 10. | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN
SHARES | ☐ |
| 11. | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.77% (3) | |
| 12. | TYPE OF REPORTING PERSON* PN | |

---

(3) Comprised of shares of common stock held by Deerfield Private Design Fund III, L.P., of which Deerfield Mgmt III, L.P. is the general partner.

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CUSIP No. 014442107 13G Page 5 of 16

1.	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) Deerfield Mgmt IV, L.P.
2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*	(a)
☐ (b) ☒
3.	SEC USE ONLY
4.	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	5.	SOLE VOTING POWER 0
	6.	SHARED VOTING POWER 527,596 (4)
	7.	SOLE DISPOSITIVE POWER 0
	8.	SHARED DISPOSITIVE POWER 527,596 (4)
9.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 527,596 (4)
10.	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN
SHARES*	☐
11.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.77% (4)
12.	TYPE OF REPORTING PERSON* PN

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(4) Comprised of shares of common stock held by Deerfield Private Design Fund IV, L.P., of which Deerfield Mgmt IV, L.P. is the general partner.

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CUSIP No. 014442107 13G Page 6 of 16

| 1. | NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) Deerfield Special
Situations Fund, L.P. | |
| --- | --- | --- |
| 2. | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP | (a)
☐ (b) ☒ |
| 3. | SEC USE ONLY | |
| 4. | CITIZENSHIP OR PLACE OF ORGANIZATION Delaware | |
| NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH | 5. | SOLE VOTING POWER 0 |
| | 6. | SHARED VOTING POWER 351,731 |
| | 7. | SOLE DISPOSITIVE POWER 0 |
| | 8. | SHARED DISPOSITIVE POWER 351,731 |
| 9. | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 351,731 | |
| 10. | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN
SHARES | ☐ |
| 11. | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.51% | |
| 12. | TYPE OF REPORTING PERSON* PN | |

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CUSIP No. 014442107 13G Page 7 of 16

1.	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) Deerfield Partners, L.P.
2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*	(a)
☐ (b) ☒
3.	SEC USE ONLY
4.	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	5.	SOLE VOTING POWER 0
	6.	SHARED VOTING POWER 550,000
	7.	SOLE DISPOSITIVE POWER 0
	8.	SHARED DISPOSITIVE POWER 550,000
9.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 550,000
10.	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN
SHARES*	☐
11.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.80%
12.	TYPE OF REPORTING PERSON* PN

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CUSIP No. 014442107 13G Page 8 of 16

1.	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) Deerfield Private Design Fund III, L.P.
2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*	(a)
☐ (b) ☒
3.	SEC USE ONLY
4.	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	5.	SOLE VOTING POWER 0
	6.	SHARED VOTING POWER 527,596
	7.	SOLE DISPOSITIVE POWER 0
	8.	SHARED DISPOSITIVE POWER 527,596
9.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 527,596
10.	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN
SHARES*	☐
11.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.77%
12.	TYPE OF REPORTING PERSON* PN

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CUSIP No. 014442107 13G Page 9 of 16

1.	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) Deerfield Private Design Fund IV, L.P.
2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*	(a)
☐ (b) ☒
3.	SEC USE ONLY
4.	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	5.	SOLE VOTING POWER 0
	6.	SHARED VOTING POWER 527,596
	7.	SOLE DISPOSITIVE POWER 0
	8.	SHARED DISPOSITIVE POWER 527,596
9.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 527,596
10.	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN
SHARES*	☐
11.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.77%
12.	TYPE OF REPORTING PERSON* PN

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CUSIP No. 014442107 13G Page 10 of 16

1.	NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) James E. Flynn
2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*	(a)
☐ (b) ☒
3.	SEC USE ONLY
4.	CITIZENSHIP OR PLACE OF ORGANIZATION United States
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	5.	SOLE VOTING POWER 0
	6.	SHARED VOTING POWER 1,956,923 (5)
	7.	SOLE DISPOSITIVE POWER 0
	8.	SHARED DISPOSITIVE POWER 1,956,923 (5)
9.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,956,923 (5)
10.	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN
SHARES*	☐
11.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 2.86%
12.	TYPE OF REPORTING PERSON* IN

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(5) Comprised of shares of common stock held by Deerfield Partners, L.P., Deerfield Special Situations Fund, L.P., Deerfield Private Design Fund III, L.P. and Deerfield Private Design Fund IV, L.P.

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CUSIP No. 014442107 13G Page 11 of 16

Item 1(a).	Name of Issuer:
	Alector, Inc.
Item 1(b).	Address of Issuer's Principal Executive Offices:
	151 Oyster Point Boulevard, Suite 300 South San Francisco, CA 94080
Item 2(a).	Name of Person Filing:
	James E. Flynn, Deerfield Mgmt, L.P., Deerfield Mgmt III, L.P., Deerfield Mgmt IV, L.P., Deerfield Management
Company, L.P., Deerfield Special Situations Fund, L.P., Deerfield Partners, L.P., Deerfield Private Design Fund III, L.P. and Deerfield
Private Design Fund IV, L.P.
Item 2(b).	Address of Principal Business Office, or if None, Residence:
	James E. Flynn, Deerfield
Mgmt, L.P., Deerfield Mgmt III, L.P., Deerfield Mgmt IV, L.P., Deerfield Management Company, L.P., Deerfield Special Situations
Fund, L.P., Deerfield Partners, L.P., Deerfield Private Design Fund III, L.P. and Deerfield
Private Design Fund IV, L.P., 780 Third Avenue, 37th Floor, New York, NY 10017
Item 2(c).	Citizenship:
	Deerfield Mgmt, L.P.,
Deerfield Mgmt III, L.P., Deerfield Mgmt IV, L.P., Deerfield Management Company, L.P., Deerfield Special Situations Fund, L.P., Deerfield Partners, L.P., Deerfield Private Design Fund III, L.P. and Deerfield Private Design
Fund IV, L.P. - Delaware limited partnerships; James E. Flynn – United States citizen
Item 2(d).	Title of Class of Securities:
	Common Stock, par value $0.0001 per share
Item 2(e).	CUSIP Number:
	014442107
Item 3.	If This Statement is Filed Pursuant to
Rule 13d-1(b), or 13d-2(b) or (c), Check Whether the Person Filing is a:
(a)	☐	Broker or dealer registered under Section 15 of the
Exchange Act.
(b)	☐	Bank as defined in Section 3(a)(6) of the Exchange Act.
(c)	☐	Insurance company as defined in Section 3(a)(19) of
the Exchange Act.
(d)	☐	Investment company registered under Section 8 of the
Investment Company Act.
(e)	☐	An investment adviser in accordance with Rule 13d-1(b)(1)(ii)(E);

(f) ☐ An employee benefit plan or endowment fund in accordance with Rule 13d-1(b)(1)(ii)(F);

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CUSIP No. 014442107 13G Page 12 of 16

| (g) | ☐ | A parent holding company or control person in accordance
with Rule 13d-1(b)(1)(ii)(G); |
| --- | --- | --- |
| (h) | ☐ | A savings association as defined in Section 3(b) of
the Federal Deposit Insurance Act; |
| (i) | ☐ | A church plan that is excluded from the definition
of an investment company under Section 3(c)(14) of the Investment Company Act; |

(j)	☐	A non-U.S. institution in accordance with Rule 13d-1(b)(1)(ii)(J);
(k)	☐	Group, in accordance with Rule 13d-1(b)(1)(ii)(K).

If filing as a non-U.S. institution in accordance with Rule 13d-1(b)(1)(ii)(J), please specify the type of institution: _____

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)	Amount beneficially owned**:
	Deerfield
Mgmt, L.P. - 901,731 shares Deerfield Mgmt III,
L.P. – 527,596 shares Deerfield Mgmt IV,
L.P. – 527,596 shares Deerfield Management
Company, L.P. - 1,956,923 shares Deerfield Special Situations
Fund, L.P. - 351,731 shares Deerfield Partners,
L.P. - 550,000 shares Deerfield Private Design
Fund III, L.P. – 527,596 shares Deerfield Private Design
Fund IV, L.P. – 527,596 shares James E. Flynn – 1,956,923 shares
(b)	Percent of class**:
	Deerfield
Mgmt, L.P. – 1.32% Deerfield Mgmt III,
L.P. – 0.77% Deerfield Mgmt IV,
L.P. – 0.77% Deerfield Management
Company, L.P. – 2.86% Deerfield Special Situations
Fund, L.P. – 0.51% Deerfield Partners,
L.P. - 0.80% Deerfield Private Design
Fund III, L.P. – 0.77% Deerfield Private Design
Fund IV, L.P. – 0.77% James E. Flynn – 2.86%
(c)	Number of shares as to which such person has**:
	(i)	Sole power to vote or to direct the vote:	All Reporting Persons - 0
	(ii)	Shared power to vote or to direct the vote:	Deerfield
Mgmt, L.P. - 901,731 shares Deerfield Mgmt III,
L.P. – 527,596 shares Deerfield Mgmt IV,
L.P. – 527,596 shares Deerfield Management
Company, L.P. - 1,956,923 shares Deerfield Special Situations
Fund, L.P. - 351,731 shares Deerfield Partners,
L.P. - 550,000 shares Deerfield Private Design
Fund III, L.P. – 527,596 shares Deerfield Private Design
Fund IV, L.P. – 527,596 shares James E. Flynn – 1,956,923 shares

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CUSIP No. 014442107 13G Page 13 of 16

(iii) Sole power to dispose or to direct the disposition of: All Reporting Persons - 0

(iv) Shared power to dispose or to direct the disposition of: Deerfield Mgmt, L.P. - 901,731 shares Deerfield Mgmt III, L.P. – 527,596 shares Deerfield Mgmt IV, L.P. – 527,596 shares Deerfield Management Company, L.P. - 1,956,923 shares Deerfield Special Situations Fund, L.P. - 351,731 shares Deerfield Partners, L.P. - 550,000 shares Deerfield Private Design Fund III, L.P. – 527,596 shares Deerfield Private Design Fund IV, L.P. – 527,596 shares James E. Flynn – 1,956,923 shares

**See footnotes on cover pages which are incorporated by reference herein.

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 ☒.
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.
	N/A
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.
	N/A

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CUSIP No. 014442107 13G Page 14 of 16

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.
	See Exhibit B
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.
	N/A
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, other than activities solely in connection
with a nomination under §240.14a–11."

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CUSIP No. 014442107 13G Page 15 of 16

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.

DEERFIELD MGMT, L.P.

By: J.E. Flynn Capital, LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

DEERFIELD MANAGEMENT COMPANY, L.P.

By: Flynn Management LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

DEERFIELD MGMT III, L.P.

By: J.E. Flynn Capital III, LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

DEERFIELD MGMT IV, L.P.

By: J.E. Flynn Capital IV, LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

DEERFIELD SPECIAL SITUATIONS FUND, L.P.

By: Deerfield Mgmt, L.P., General Partner

By: J.E. Flynn Capital, LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

DEERFIELD PARTNERS, L.P.

By: Deerfield Mgmt, L.P., General Partner

By: J.E. Flynn Capital, LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

DEERFIELD PRIVATE DESIGN FUND III, L.P.

By: Deerfield Mgmt III, L.P., General Partner

By: J.E. Flynn Capital III, LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

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CUSIP No. 014442107 13G Page 16 of 16

DEERFIELD PRIVATE DESIGN FUND IV, L.P.

By: Deerfield Mgmt IV, L.P., General Partner

By: J.E. Flynn Capital IV, LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

JAMES E. FLYNN

/s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

Date: February 11, 2019

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Exhibit List

Exhibit A. Joint Filing Agreement.

Exhibit B. Item 8 Statement.

Exhibit C. Power of Attorney (1).

(1) Power of Attorney previously filed as Exhibit 24 to a Form 3 with regard to Proteon Therapeutics, Inc. filed with the Securities and Exchange Commission on August 4, 2017 by Deerfield Special Situations Fund, L.P., Deerfield Partners, L.P., Deerfield International Master Fund, L.P., Deerfield Private Design Fund III, L.P., Deerfield Private Design Fund IV, L.P., Deerfield Mgmt, L.P., Deerfield Mgmt III, L.P., Deerfield Mgmt IV, L.P., Deerfield Management Company, L.P., and James E. Flynn.

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Exhibit A

Joint Filing Agreement

The undersigned agree that this Schedule 13G, and all amendments thereto, relating to the Common Stock, par value $0.0001 per share, of Alector, Inc. shall be filed on behalf of the undersigned.

DEERFIELD MGMT, L.P.

By: J.E. Flynn Capital, LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

DEERFIELD MANAGEMENT COMPANY, L.P.

By: Flynn Management LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

DEERFIELD MGMT III, L.P.

By: J.E. Flynn Capital III, LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

DEERFIELD MGMT IV, L.P.

By: J.E. Flynn Capital IV, LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

DEERFIELD SPECIAL SITUATIONS FUND, L.P.

By: Deerfield Mgmt, L.P., General Partner

By: J.E. Flynn Capital, LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

DEERFIELD PARTNERS, L.P.

By: Deerfield Mgmt, L.P., General Partner

By: J.E. Flynn Capital, LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

DEERFIELD PRIVATE DESIGN FUND III, L.P.

By: Deerfield Mgmt III, L.P., General Partner

By: J.E. Flynn Capital III, LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

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DEERFIELD PRIVATE DESIGN FUND IV, L.P.

By: Deerfield Mgmt IV, L.P., General Partner

By: J.E. Flynn Capital IV, LLC, General Partner

By: /s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

JAMES E. FLYNN

/s/ Jonathan Isler

Jonathan Isler, Attorney-In-Fact

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Exhibit B

Due to the relationships between them, the reporting persons hereunder may be deemed to constitute a “group” with one another for purposes of Section 13(d)(3) of the Securities Exchange Act of 1934.