UBS Securities LLC
J.P. Morgan Securities Inc.
Leerink Swann & Co., Inc.
Pacific Growth Equities, LLC
As Representatives of the severa
Underwriters
c/o UBS Securities LLC
299 Park Avenue
New York, NY 10171
May 18, 2007
6,210,000 Shares
HELICOS BIOSCIENCES CORPORATION
Common Stock
Securities and Exchange Commission
100 F Street, N.E.
Washington, DC 20549
Ladies and Gentleman:
Pursuant to Rule 461 under the Securities Act of 1933, as amended, the undersigned, as the representatives of the prospective Underwriters of the above-captioned Shares, hereby join in the request of Helicos BioSciences Corporation that the effectiveness of the Registration Statement on Form S-1 relating to such Shares (Registration No. 333-140973) be accelerated so that the Registration Statement will become effective by 2:00 p.m. on May 22, 2007 or as soon thereafter as practicable.
[The Remainder of This Page Intentionally Left Blank; Signature Page Follows]
| Very truly yours, | |
|
| |
| UBS SECURITIES LLC | |
| J.P. MORGAN SECURITIES INC. | |
| LEERINK SWANN & CO., INC. | |
| PACIFIC GROWTH EQUITIES, LLC | |
|
|
|
| By: | UBS SECURITIES LLC |
|
|
|
| By: | /s/ Steven Meehan |
|
| Name: Steven Meehan |
|
| Title: Managing Director |
|
|
|
| By: | /s/ Peter Lang |
|
| Name: Peter Lang |
|
| Title: Executive Director |
