Exhibit 10.5 SECOND AMENDMENT TO STANDARD INDUSTRIAL/COMMERCIAL MULTI-TENANT LEASE - GROSS  THIS AMENDMENTMADE
THIS 22TH DAY OF November, 2002 (the Amendment) by and between WDI SANTA MONICA LLC, A CALIFORNIA LIMITED LIABILITY
CORPORATION,hereinafter referred to as Lessor, and SPECIALTY LABORATORIES, INC., A CALIFORNIA
CORPORATION, Hereinafter referred to as Lessee.  WITNESSETH:  WHEREAS, Lessee
entered into a certain Standard Industrial/Commercial Multi-Tenant Lease-Gross
(Lease), dated January 26, 2000, with Lessor leasing certain premises
commonly known as 1756 22ndStreet, Santa Monica, California 90404;
and  WHEREAS,said Lease
was amended in certain particulars by First Amendment To Lease, dated July 15,
2000; and  WHEREAS, Lessor and
Lessee are desirous of amending said amended Lease by this Second Amendment to
Lease in the manner set forth below.  NOW THEREFORE, in
consideration of the mutual promises herein contained, Lessor and Lessee hereby
agree to amend said Lease as follows:  1.             TERM  The term in
Paragraph 1.3 of the Lease, as amended, shall be extended for one (1) year,
terminating June 30, 2004.  2.             BASE RENTAL  The Base
Rental set forth in Paragraph 1.6 of the Lease, as amended, shall be increased
as follows:  (a)For the Premises existing as of the date
of this Amendment the Base Rental shall be increased starting on July 1, 2003
through June 30, 2004 to $7,250.00 per month.  3.             OPTION TO EXTEND  The Option to
Extend in Paragraph 60 of the Lease shall be deleted in its entity and shall be
replaced with the following:  Lessor hereby
grants to Lessee the option to extend the term of this Lease for two (2)
additional twelve (12) month period(s) commencing when the prior term expires
upon each and all of the following terms and conditions:  (a)In order to exercise an option to
extend, Lessee must give written notice of such election to Lessor and Lessor
must receive the same at least five (5) but not more than nine (9) months prior
to the date that the option period would commence, time being of the
essence.  If proper notification of the
exercise of an option is not given and/or received, such option shall
automatically expire.  Options (if there
are more than one) may only be exercised consecutively.  (b)The provisions of paragraph 39, including
those relating to Lessees Default set forth in paragraph 39.4 of this Lease,
are conditions of this Option.  (c)Except for the provisions of this Lease
granting an option or options to extend the term, all of the terms and
conditions of this Lease except where specifically modified by this option
shall apply.  1 
   (d)This Option is personal to the original
Lessee, and cannot be assigned or exercised by anyone other than said original
Lessee (or in the event of a merger, acquisition, sale of all or substantially
all of Lessees assets, or similar transaction, Lessees successors) and only
while the original Lessee is in full possession of the Premises and without the
intention of thereafter assigning or subletting.  (e)In the event Lessee exercises the option
herein, the monthly Base Rental shall be increased to the following amounts on
the dates set forth below.  On:
  
  The new Base
  Rental shall be:July 1, 2004
  
  $7,467.50April 1, 2005
  
  $7,692.00   4.             NOTICE  Unless
specified otherwise herein, notice of any rental adjustments, other than Fixed
Rental Adjustments, shall be made as specified in Paragraph 23 of the
Lease.  A copy of any notices sent by
Lessor shall also be sent to the Office of the General Counsel at the same
address as Lessee.  5.             BROKERS FEE  The Brokers
specified in paragraph 1.10 shall be paid a Brokerage Fee for each adjustment
specified above in accordance with paragraph 15 of the Lease.  IN WITNESS WHEREOF,
Lessor and Lessee have caused this Second Amendment to Lease to be executed on
the day and year first above written.  WDI SANTA MONICA LLC,
  SPECIALTY LABORATORIES, INC.,A CALIFORNIA LIMITED
  A CALIFORNIA CORPORATIONLIABILITY CORPORATIONLESSOR:
  LESSEE:By:
  /s/  Warren A. Weiss
  By:
  /s/  Frank J. SpinaWarren A. Weiss, Managing Member
  
  Frank J. Spina CFODate
  12/1/02
  Date:
  11/25/02  2