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                                                                   Exhibit 10.10

                          TRADEMARK LICENSE AGREEMENT


          THIS TRADEMARK LICENSE AGREEMENT (the "Agreement") is made and entered
into as of June 10, 2001 by and between SeraCare, Inc., a Delaware corporation
("SeraCare" or "Licensor") and SeraCare Life Sciences, Inc., a California
corporation ("Life Sciences" or "Licensee").

                                   RECITALS
                                   --------

          WHEREAS, SeraCare owns the mark set forth in Exhibit A attached hereto
and incorporated herein by reference (the "Mark") and has used the Mark as
trademark, service mark and trade name in connection with the SeraCare Business;
and

          WHEREAS, in connection the Agreement and Plan of Merger between
SeraCare and Instituto Grifols, S.A., a company organized under the laws of
Spain ("Grifols"), pursuant to which SeraCare will merge with SI Merger Corp., a
Delaware corporation and wholly-owned subsidiary of Grifols (the "Merger"),
dated June 10, 2001, SeraCare desires to license to Life Sciences the Mark for
use in connection with the Life Sciences Business.

          NOW, THEREFORE, in consideration of the recitals above, and the mutual
promises set forth below, the parties hereto agree as follows:

          1.  License.  Licensor hereby grants to Licensee an exclusive license
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(the "License") to use the Mark in connection with the Life Sciences Business
for the Term (as defined below) in any territory throughout the world in
accordance with the terms and conditions set forth in this Agreement.  Licensee
and Licensor acknowledge that the License is exclusive and, as such, Licensor
shall not sell or license to others the Mark in any manner whatsoever, except in
accordance with Section 13.  Nothing herein shall be intended to prevent
Licensor from using the Mark in the SeraCare Business.

          2.  Term of License.  The term of the License shall commence as of the
              ---------------
date hereof and, shall continue perpetually unless Licensor notifies Licensee in
writing that this Agreement is terminated, pursuant to Paragraph 9 below (the
"Term").

          3.  Ownership and Use of Mark.
              -------------------------

              a.  Licensee shall not use the Mark in a manner that materially
(i) contravenes any statute or regulation, (ii) impairs the validity or
enforceability of the Mark; (iii) impairs the quality of products and services
with which the Mark is used; or (iv) disparages the Mark or Licensor. Licensee
agrees that all proprietary right and goodwill in any Mark shall
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inure solely to the benefit of Licensor, that the uses of the Mark by Licensee
shall not create any interest or right, express or implied, in the Mark in
Licensee except as set forth in this Agreement, and that Licensee does not and
will not assert any claim to any ownership thereof. If, by operation of law, or
otherwise, Licensee is deemed to or appears to own any property rights in the
Mark, Licensee shall, at Licensor's request, execute any and all documents
necessary to confirm or otherwise establish Licensor's rights therein. Licensee
agrees to cooperate with any reasonable request made by Licensor to help
register, maintain and/or enforce Licensor's title and rights in and to the
Mark.

               b. During the term of this Agreement or at any time thereafter,
Licensee shall not dispute or contest, or assist any other party in disputing or
contesting, the validity or enforceability of Licensor's right, title and
interest in and to the Mark.  This includes an agreement that Licensee shall not
oppose or assist another in opposing any application filed by Licensor for
registration of the Mark, and shall not take any action to cancel or assist
another in canceling any trademark registration obtained by Licensor for the
Mark.

          4.   [INTENTIONALLY OMITTED.].

          5.   Quality Control.  The quality of all products and services
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offered by Licensee using the Mark ("Goods and Services") shall meet or exceed
industry standards in all material respects.  Licensee shall cooperate with all
reasonable requests by Licensor to ensure compliance with the terms of this
Agreement.  If Licensor reasonably determines that any material aspect of the
Goods and Services, or Licensee's use of the Mark in connection with the
advertising or sale of the Goods and Services, does not meet or exceed industry
standards in all material respects, then Licensor shall notify Licensee in
writing specifying such deficiencies.  If Licensee does not correct all such
deficiencies to Licensor's reasonable satisfaction within ninety days (90), then
Licensor may terminate this Agreement pursuant to Paragraph 9(b) below.

          6.   Foreign Qualifications.  The parties hereby agree that Life
               ----------------------
Sciences shall have the right to qualify to do business as a foreign corporation
in every state in the United States under the name "SeraCare Life Sciences,
Inc."  If any state prohibits such qualification on the grounds that the Mark is
in use by SeraCare, then SeraCare shall change its qualification in such state
in order to permit Licensee to qualify in such state, provided that Licensee
shall pay SeraCare's reasonable costs and expenses in connection therewith.

          7.   Infringement Actions.  In the event that either party learns of
               --------------------
any actual or potential infringement, misuse or misappropriation of the Mark,
such party shall promptly notify the other thereof in writing.  In such event,
Licensor shall have the right to institute legal action and, at its option,
and/or as may be required by law, join Licensee as plaintiff.  Licensor may
select counsel of its choice, and shall control the action and shall bear the
entire costs of such action, and shall be entitled to retain the entire amount
of any recovery by way of judgment, award, decree or settlement.  If Licensor
determines not to institute legal action, Licensee may institute legal action;
provided, however that Licensee agrees to indemnify and hold Licensor harmless
from and against any and all liabilities, damages, judgments, penalties, losses,
costs, expenses, claims, suits or demands relating to or arising out of such
legal action.  In such event,

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Licensee may select counsel of its choice, and shall control the action and
shall bear the entire cost of such action, and shall be entitled to retain the
entire amount of any recovery by way of judgment, award, decree or settlement.
Each party shall cooperate with the other party in any such actions against
third parties, and may if such party desires, elect to be represented by counsel
of its choice, but at its own expense.

          8.   Indemnification.
               ---------------

               a.   Licensee will protect, defend, indemnify and hold Licensor,
its parents, subsidiaries, affiliates, and the officers, directors, employees,
shareholders and agents of each of them, harmless from and against any and all
liabilities, damages, judgments, penalties, losses, costs, expenses (including
without limitation reasonable attorneys' fees), claims, suits, or demands
relating to or arising from any breach by Licensee of any of its agreements
hereunder or by reason of the use by Licensee of the Mark.

               b.   Licensor will protect, defend, indemnify and hold Licensee,
its parents, subsidiaries, affiliates, and the officers, directors, employees,
shareholders and agents of each of them, harmless from and against any and all
liabilities, damages, judgments, penalties, losses, costs, expenses (including
without limitation reasonable attorneys' fees), claims, suits, or demands
relating to or arising from any breach by Licensor of any of its agreements in
Sections 1, 6, 7, 12 and 13 hereunder.

          9.   Termination.  Licensee may terminate this Agreement at any time
               -----------
upon thirty (30) days written notice to Licensor.  Licensor may terminate this
Agreement upon written notice effective immediately, if Licensee commits any
material breach of this Agreement and fails to cure the breach within ninety
(90) days after receipt of Licensor's written request to do so.

          10.  Effect of Termination.  Termination of this Agreement for cause
               ---------------------
shall be without prejudice to any other remedy otherwise available to the
parties to this Agreement.  Upon termination of this Agreement for any reason,
Licensee agrees to discontinue all use of the Mark and to refrain from using any
confusingly similar or conflicting trademarks, service marks, trade names and/or
other indicia of origin.

          11.  Notices.  All notices and other communications hereunder shall be
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in writing and shall be given (and shall be deemed to have been duly given upon
receipt) by delivery in person by telegram, telecopy, telex or other standard
form of telecommunications (with telephonic confirmed receipt of such
telecommunication), or by registered or certified mail, postage prepaid, return
receipt requested to the address of the headquarters of the receiving party.

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          12.  Assignments.  This Agreement and all of the provisions hereof
               -----------
shall be binding upon and inure to the benefit of the parties hereto and their
respective successors and permitted assigns.  Subject to Section 13, neither
this Agreement nor any of the rights, interests or obligations of Licensee or
Licensor hereunder shall be assigned, sublicensed, or transferred without the
prior written consent of the other party, which consent may not be unreasonably
withheld.  However, in the event Licensor sells to a single purchaser all or
substantially all of the assets of the Licensor, Licensor may sell the Mark to
such purchaser in connection with such sale without the consent of Licensee, and
without regard to Section 13, subject to assumption of the obligations of
Licensor under this Agreement.

          13.  Right of First Refusal.  In the event that Licensor ceases to use
               ----------------------
the Mark in connection with the SeraCare Business, Licensor may transfer or
assign the Mark to a third party in the SeraCare Business only on the following
terms and conditions:

               (a) If the Licensor intends to transfer or assign the Mark, the
Licensor shall deliver written notice of such intention to Licensee.  Such
notice (the "Offer Notice") shall state the proposed purchase price, the name of
the proposed transferee and the terms and conditions of the transfer of the
Mark.

               (b) For a period of thirty (30) days after receipt of the Offer
Notice (the "Offer Period"), Licensee may, by written notice to the Licensor
(the "Acceptance Notice"), elect to purchase the Mark for an aggregate purchase
price equal to the price specified in the Offer Notice.

               (c) If the Licensee fails to deliver the Acceptance Notice to the
Licensor prior to the expiration of the Offer Period, then, for a period of
ninety (90) days from the expiration of the Offer Period, the Licensor may
transfer or assign the Mark only in accordance with the terms of the Offer
Notice. If such transfer does not occur on or before the expiration of the
ninety day period, then Licensor must deliver another Offer Notice pursuant to
Section 13(a).

               (d) At the closing of the purchase of the Mark pursuant to
Section 13(b), which shall take place within thirty days of delivery of the
Acceptance Notice, Licensee shall deliver to the Licensor, against delivery by
Licensor of appropriate instruments of transfer of the Mark, the purchase price
of the Mark specified in the Acceptance Notice.

          14.  Injunctive Relief.  Licensee acknowledges that, in the event of
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any unauthorized use of the Mark by Licensee, money damages alone would be
inadequate and, therefore, Licensor shall, in addition to such other collateral,
legal and equitable rights and remedies as may be available to it, have the
right to injunctive relief without being required to prove damages or furnish a
bond or other security.

          15.  Independent Contracting Parties.  The parties are and shall be
               -------------------------------
independent contractors to one another and nothing in the Agreement shall create
an agency, partnership or joint venture between the parties.

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          16.  No Waiver.  No failure by either party to take action on account
               ---------
of any default by the other, whether in a single instance or repeatedly, shall
constitute a waiver of any such default or the performance required of such
party.  No express waiver of a default by any party shall be construed as a
waiver of any other default or future performance required hereunder.

          17.  Headings.  The headings contained in this Agreement are inserted
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for convenience only and do not constitute a part of this Agreement.

          18.  Invalidity.  If any provision of this Agreement is held invalid
               ----------
or unenforceable, the remainder of this Agreement shall nevertheless remain in
full force and effect.

          19.  Entire Agreement.  This Agreement (including the instruments
               ----------------
between the parties referred to herein) constitutes the complete, final and
exclusive statement of the entire agreement among the parties and supersedes all
other prior agreements and understandings, both written and oral, with respect
to the subject matter hereof.  This Agreement may not be amended or supplemented
in any manner except by a written agreement executed by an authorized
representative of the party sought to be bound.  All references to paragraphs,
sections, subsections, clauses and schedules shall be deemed to refer to such
part of this Agreement, unless the context requires otherwise.

          20.  Governing Law.  This Agreement and the legal relations between
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the parties hereto shall be governed by and construed in accordance with the
internal laws of the State of California and without regard to conflict of laws
principles.

          21.  Jurisdiction.  The courts of the State of California, including
               ------------
the federal courts sitting in the State of California, shall have exclusive
jurisdiction to hear and decide all controversies that may arise under or
concerning this Agreement.

          22.  Counterparts.  This Agreement may be executed in any number of
               ------------
counterparts, each of which shall be deemed to be an original but all of which
together shall constitute but one agreement.

          23.  Definitions.
               -----------

               a.  "Life Sciences Business" means the business and organization
     for the manufacturing, marketing and selling of therapeutic based blood
     plasma products, diagnostic test kits, specialty plasma used for diagnostic
     purposes and bulk materials, and shall not include the business of
     collecting blood plasma.

               b.  "SeraCare Business" means the business of collecting blood
     plasma.

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          IN WITNESS WHEREOF, the authorized representatives of the parties
hereto have duly executed this Agreement as of the first date above.

LICENSOR:                               LICENSEE:
--------                                --------

SeraCare, Inc.                          SeraCare Life Sciences, Inc.


By:   /s/ Barry Plost                   By:   /s/ Jerry L. Burdick
      -----------------------                 ------------------------
Name: Barry Plost                       Name: Jerry L. Burdick
Its:  Chief Executive Officer           Its:  Executive Vice President

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                                   EXHIBIT A

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