SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
 
Schedule 13G
 
Under the Securities Exchange Act of 1934
(Amendment No.: 1 )*

 
Name of issuer:  Penumbra Inc

Title of Class of Securities:  Common Stock

CUSIP Number:  70975L107

Date of Event Which Requires Filing of this Statement: December 31, 2017
 
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
  (X) Rule 13d-1(b)
  (  ) Rule 13d-1(c)
  (  ) 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).

(Continued on the following page(s))

 
13G
CUSIP No.:  70975L107

1.  NAME OF REPORTING PERSON
  S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
 
  The Vanguard Group - 23-1945930
 
2.  CHECK THE APPROPRIATE [LINE] IF A MEMBER OF A GROUP

A.	B.  X	
 
3.  SEC USE ONLY

 
4.  CITIZENSHIP OF PLACE OF ORGANIZATION
 
  Pennsylvania
 
(For questions 5-8, report the number of shares beneficially owned by each reporting person with:)
 
5.  SOLE VOTING POWER
 
  56,944
 
6.  SHARED VOTING POWER
 
  4,900
 
7.  SOLE DISPOSITIVE POWER
 
  2,438,522
 
8.  SHARED DISPOSITIVE POWER
 
   59,626
 
9.  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
  2,498,148
 
10.  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
 
  N/A
 
11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
 
  7.36%
 
12.  TYPE OF REPORTING PERSON
 
  IA

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
 
SCHEDULE 13G
Under the Securities Act of 1934
 
Check the following [line] if a fee is being paid with this statement   N/A
 
Item 1(a) - Name of Issuer:
 
  Penumbra Inc

Item 1(b) - Address of Issuer's Principal Executive Offices:
 
  One Penumbra Place
  Alameda, CA 94502
 
Item 2(a) - Name of Person Filing:
 
  The Vanguard Group - 23-1945930
 
Item 2(b) – Address of Principal Business Office or, if none, residence:
 
  100 Vanguard Blvd.
  Malvern, PA  19355
 
Item 2(c) – Citizenship:
 
  Pennsylvania
 
Item 2(d) - Title of Class of Securities:
 
  Common Stock
 
Item 2(e) - CUSIP Number
 
  70975L107
 
Item 3 - Type of Filing:
 
  This statement is being filed pursuant to Rule 13d-1.  An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E).
 
Item 4 - Ownership:
 
  (a) Amount Beneficially Owned:
 
  2,498,148
 
  (b) Percent of Class:
 
  7.36%

  (c)  Number of shares as to which such person has:
 
  (i)  sole power to vote or direct to vote:  56,944
 
  (ii)  shared power to vote or direct to vote:  4,900
 
  (iii)  sole power to dispose of or to direct the disposition of:  2,438,522
 
  (iv)  shared power to dispose or to direct the disposition of:  59,626
 
Comments:

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 :
 
  See Attached Appendix A
 
Item 8 - Identification and Classification of Members of Group:
 
  Not applicable
 
Item 9 - Notice of Dissolution of Group:
 
  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 acquired in the ordinary course of business and were not acquired for the purpose of and do not have the effect of changing or influencing the control of the issuer of such securities and were not acquired 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.
 
Date:  02/07/2018
 
By /s/ Christine M. Buchanan
Name: Christine M. Buchanan
Title:  Principal

 
Appendix A
 
 Vanguard Fiduciary Trust Company ("VFTC"), a wholly-owned subsidiary of The Vanguard Group, Inc., is the beneficial owner of  54,726 shares or  .16% of the Common Stock outstanding of the Company as a result of its serving as investment manager of collective trust accounts.
 
Vanguard Investments Australia, Ltd. ("VIA"), a wholly-owned subsidiary of The Vanguard Group, Inc., is the beneficial owner of  7,118 shares or  .02% of the Common Stock outstanding of the Company as a result of its serving as investment manager of Australian investment offerings.