0001140361-12-004244.txt : 20120130 0001140361-12-004244.hdr.sgml : 20120130 20120130132736 ACCESSION NUMBER: 0001140361-12-004244 CONFORMED SUBMISSION TYPE: SC 13G PUBLIC DOCUMENT COUNT: 1 FILED AS OF DATE: 20120130 DATE AS OF CHANGE: 20120130 SUBJECT COMPANY: COMPANY DATA: COMPANY CONFORMED NAME: NxStage Medical, Inc. CENTRAL INDEX KEY: 0001333170 STANDARD INDUSTRIAL CLASSIFICATION: ELECTROMEDICAL & ELECTROTHERAPEUTIC APPARATUS [3845] IRS NUMBER: 043454702 STATE OF INCORPORATION: DE FISCAL YEAR END: 1231 FILING VALUES: FORM TYPE: SC 13G SEC ACT: 1934 Act SEC FILE NUMBER: 005-81212 FILM NUMBER: 12554850 BUSINESS ADDRESS: STREET 1: 439 SOUTH UNION STREET STREET 2: 5TH FLOOR CITY: LAWRENCE STATE: MA ZIP: 01843 BUSINESS PHONE: 978-687-4700 MAIL ADDRESS: STREET 1: 439 SOUTH UNION STREET STREET 2: 5TH FLOOR CITY: LAWRENCE STATE: MA ZIP: 01843 FILED BY: COMPANY DATA: COMPANY CONFORMED NAME: BLAIR WILLIAM & CO/IL CENTRAL INDEX KEY: 0000902367 STANDARD INDUSTRIAL CLASSIFICATION: UNKNOWN SIC - 0000 [0000] IRS NUMBER: 362214610 STATE OF INCORPORATION: DE FISCAL YEAR END: 1231 FILING VALUES: FORM TYPE: SC 13G BUSINESS ADDRESS: STREET 1: 222 WEST ADAMS ST CITY: CHICAGO STATE: IL ZIP: 60606-5312 BUSINESS PHONE: 3122361600 MAIL ADDRESS: STREET 1: 222 WEST ADAMS CITY: CHICAGO STATE: IL ZIP: 60606 SC 13G 1 doc1.htm NONE Schedule 13G
 
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
 
SCHEDULE 13G
 
 
Under the Securities Exchange Act of 1934
(Amendment No. n/a )*
 
NxStage Medical, Inc. 
(Name of Issuer)
 
Common
(Title of Class of Securities)
 
67072V103
(CUSIP Number)
 
December 31, 2011
(Date of Event Which Requires Filing of this Statement)
 
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
 
     x  Rule 13d-1(b)
 
     o  Rule 13d-1(c)
 
     o  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).
 
 
 
 
 
CUSIP No.  67072V103      
 
      
1 NAMES OF REPORTING PERSONS
I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)
 William Blair
36-2214610
   
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

 (a)   o
 (b)   o
   
3 SEC USE ONLY
  
  
   
4 CITIZENSHIP OR PLACE OF ORGANIZATION
  
 222 W. Adams, Chicago, IL 60606
    
NUMBER OF SHARES BENEFICIALLY  OWNED BY EACH REPORTING PERSON WITH: 5 SOLE VOTING POWER
  
 3,230,342
   
6 SHARED VOTING POWER
  
 0
   
7 SOLE DISPOSITIVE POWER
  
 3,230,342
   
8 SHARED DISPOSITIVE POWER
  
 0
   
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
  
 3,230,342
   
10 CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
  
 o
   
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
  
 5.85%
   
12 TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
  
 BD ,  IA
 

FOOTNOTES
  
 
 
 
 
 
Item 1.

 
(a)
Name of Issuer
 
 
NXSTAGE MEDICAL, INC.

 
(b)
Address of Issuer’s Principal Executive Offices
 
 
439 South Union Street, 5th Floor, Lawrence, MA 01843, United States

Item 2.

 
(a)
Name of Person Filing
 
 
WILLIAM BLAIR & COMPANY, L.L.C.

 
(b)
Address of Principal Business Office or, if none, Residence
 
 
222 W. Adams, Chicago, IL 60606

 
(c)
Citizenship
 
 
USA

 
(d)
Title of Class of Securities
 
 
Common

 
(e)
CUSIP Number
 
 
67072V103

 
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:

 
(a)
x
Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).

 
(b)
o
Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).

 
(c)
o
Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).

 
(d)
o
Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C 80a-8).

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

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

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

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

 
(i)
o
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);

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

 
(k)
o
A group, in accordance with § 240.13d-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.
 
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: 3,230,342

 
(b)
Percent of class: 5.85

 
(c)
Number of shares as to which the person has:

 
(i)
Sole power to vote or to direct the vote: 3,230,342

 
(ii)
Shared power to vote or to direct the vote: 0

 
(iii)
Sole power to dispose or to direct the disposition of: 3,230,342

 
(iv)
Shared power to dispose or to direct the disposition of: 0

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 o .
 
No
 
Item 6.
Ownership of More than Five Percent on Behalf of Another Person.
 
n/a
 
Item 7.
Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company
 
n/a
 
Item 8.
Identification and Classification of Members of the Group
 
n/a
 
Item 9.
Notice of Dissolution of Group
 
n/a
 
 
 
 
 
 
Item 10.
Certification
  
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and 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.
 
 

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: January 24, 2012
By:
/s/  Michelle Seitz 
   Name: Michelle Seitz 
   Title:  Principal & Head of Investment Management 
    
 
Footnotes:

Attention:
Intentional misstatements or omissions of fact constitute Federal criminal violations (See 18 U.S.C. 1001)