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EXHIBIT 6.20

                              EMPLOYMENT AGREEMENT

         This Employment Agreement (this "AGREEMENT") is entered into as of
September 9, 1999 (the "EFFECTIVE DATE"), by and between James Linesch (the
"EXECUTIVE") and SeraCare, Inc., a Delaware corporation (the "COMPANY").

                                    RECITALS

         The Company desires that the Executive be employed by the Company in
the capacities described below, on the terms and conditions hereinafter set
forth, and the Executive is willing to accept such employment on such terms and
conditions.

                                    AGREEMENT

         The Executive and the Company agree as follows:

1.       DUTIES.

1.1      RETENTION. The Company does hereby hire, engage, and employ the
         Executive as the Chief Financial Officer of the Company, and the
         Executive does hereby accept and agree to such hiring, engagement, and
         employment. During the Period of Employment (as defined in Section 2),
         the Executive shall serve the Company in such position, and shall have
         duties and authority consistent with such position (including primary
         general authority over the Company's finance department), subject,
         however, to the other provisions of this Agreement, directives of the
         Chief Executive Officer of the Company (the "CEO") and/or the Board of
         Directors of the Company (the "BOARD"), and the corporate policies and
         budgets of the Company as they presently exist, and as such policies
         and budgets may be amended, modified, changed, or adopted during the
         Period of Employment. During the Period of Employment, the Executive
         shall report to the CEO. The current corporate office location is 1925
         Century Park East, Suite 1970, Los Angeles, CA.

1.2      NO OTHER EMPLOYMENT. Throughout the Period of Employment, the Executive
         shall devote his full business time, energy, and skill to the
         performance of his duties for the Company (vacations and other leave
         authorized under this Agreement excepted) and shall devote his best
         efforts to advancing the interests of the Company. The Executive agrees
         that any appointment to or continuing service on the board of directors
         of any corporation must be approved in writing by the Company, such
         approval not to be unreasonably withheld if the Company determines that
         such appointment should not interfere with the performance of the
         Executive's duties hereunder; PROVIDED that the Company's advance
         approval is

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         not required for the Executive to serve on the board of directors or
         as an officer of any non-profit trade association, or of any
         non-profit civic, educational or other charitable organization (in
         each case subject to the following sentence). The Executive's
         continued membership on any board or in any other position
         referenced in the preceding sentence, on or in which he may now or
         in the future serve (including Tadeo Holdings, Inc.), is subject to
         the conditions (a) that the Executive's membership or position does
         not materially interfere with the performance of the Executive's
         duties hereunder, and (b) that the entity with which the Executive
         is affiliated does not compete (within the meaning of Section 11,
         without giving effect to the last sentence thereof) with the
         business of any entity within the Company Group. For purposes of
         this Agreement, the "COMPANY GROUP" includes, collectively, the
         Company and any subsidiary or affiliate of the Company.

         Executive has disclosed that he is a member of the Board of Directors
         of Tadeo Holdings, Inc. and that the Company hereby approves the
         continuing service as a Board Member of that company.

1.3      NO BREACH OF CONTRACT. The Executive hereby represents to the Company
         that his execution and delivery of this Agreement and the performance
         of his duties hereunder will not constitute a breach of, or otherwise
         contravene, the terms of any employment or other agreement or policy to
         which the Executive is a party or otherwise bound. The Company hereby
         represents to the Executive that it is authorized to enter into this
         Agreement and that the execution and delivery of this Agreement and the
         employment of the Executive hereunder will not constitute a breach of,
         or otherwise contravene, the terms of any law, agreement or policy by
         which it is bound.

2.       PERIOD OF EMPLOYMENT.

         The "PERIOD OF EMPLOYMENT" shall, unless sooner terminated as provided
         herein, be a one (1) year period commencing on the Effective Date and
         ending at the close of business on the day before the first (1st)
         anniversary of the Effective Date. Notwithstanding the preceding
         sentence, commencing on the first anniversary of the Effective Date and
         each anniversary thereof (each an "EXTENSION DATE"), the Period of
         Employment shall be automatically extended for an additional one-year
         period, unless the Company or the Executive provides the other party
         hereto at least four (4) months prior written notice before the next
         scheduled Extension Date that the Period of Employment shall not be so
         extended. The term "Period of Employment" shall include any extension
         that becomes applicable pursuant to the preceding sentence.

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3.       COMPENSATION.

3.1      BASE SALARY AND BONUS. The Executive's initial Base Salary shall be at
         a rate of $140,000 annually, paid in accordance with the Company's
         regular payroll practices in effect from time to time, but not less
         frequently than in monthly installments. (As used in this Agreement,
         "Base Salary" shall mean Base Salary as it may be increased by the
         Company, in its discretion, from time to time.) The Executive's Base
         Salary, as in effect from time to time, shall not be decreased for any
         reason or for any purpose (including for purposes of determining any
         amounts due to the Executive upon a termination of his employment)
         during the Period of Employment.

         The Executive shall be eligible and considered for bonuses under the
         Company's management bonus program, which generally provides for annual
         bonuses based on the Company's profitability, the amount of any such
         bonus determined in the Company's sole discretion.

3.2      EQUITY COMPENSATION. As soon as administratively practicable after the
         Effective Date, the Executive shall be granted stock options to
         purchase 100,000 shares of the Company's Common Stock, par value $0.001
         per share (the "COMMON STOCK").

         The per share exercise price of each option granted pursuant to this
         Section 3.2 shall be at $4.25 per share, equal the fair market value of
         a share of Common Stock as of the date of grant of the option. Such
         options shall have a term of five years and shall vest in accordance
         with the following schedule, subject to the Executive's continued
         employment by the Company: 25% of the aggregate number of shares
         subject to the options shall vest and become exercisable, subject to
         the Executive's continued employment by the Company, on each of
         December 9, 1999, March 9, 2000, June 9, 2000, and September 8, 2000.
         Such options shall be granted under the SeraCare, Inc. 1998 Stock
         Option Plan, and (a) shall be granted subject to the terms of such plan
         and (b) shall be evidenced by and subject to the terms of a form of
         stock option agreement customarily used by the Company for employee
         stock option grants under the Stock Option Plan. Notwithstanding any
         termination of employment provisions in the SeraCare, Inc. 1998 Stock
         Option Plan or any customary form of stock option agreement thereunder,
         if the Executive's employment by the Company terminates (for any reason
         whatsoever): (x) before the first anniversary of the Effective Date,
         each option granted pursuant to this Section 3.2 shall terminate
         immediately to the extent that it is not then vested, and, to the
         extent that it may then be vested, it shall continue to be exercisable
         only for the ninety (90) day period following the termination of the
         Executive's employment, at which time it shall terminate to the extent

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         not exercised; and (y) on or after the first anniversary of the
         Effective Date, each option granted pursuant to this Section 3.2 shall
         continue to be exercisable for the remainder of its term.

         To the extent (if any) that the Period of Employment is extended beyond
         the first anniversary of the Effective Date, the Executive shall be
         considered for additional annual stock option grants in accordance with
         the policies and procedures of the Company then in effect for executive
         stock option grants.

4.       BENEFITS.

4.1      HEALTH AND WELFARE. During the Period of Employment, the Executive
         shall be entitled to participate in all employee pension and welfare
         benefit plans and programs generally made available to the Company's
         executive management, as such plans or programs may be in effect from
         time to time, including, without limitation, pension, profit sharing,
         savings and other retirement plans or programs, medical, dental,
         hospitalization, short-term and long-term disability and life insurance
         plans, accidental death and dismemberment protection, travel accident
         insurance, and any other pension or retirement plans or programs and
         any other employee welfare benefit plans or programs that may be
         sponsored by the Company from time to time, including any plans that
         supplement the above-listed types of plans or programs, whether funded
         or unfunded. Executive's employee and his family's welfare benefit plan
         premiums and costs shall be paid fully by the Company.

4.2      REIMBURSEMENT OF BUSINESS AND OTHER EXPENSES; PERQUISITES

         4.2.1    EXPENSE REIMBURSEMENT. The Executive is authorized to incur
                  reasonable expenses in carrying out his duties and
                  responsibilities under this Agreement and the Company shall
                  promptly reimburse him for all business expenses incurred in
                  connection with carrying out the business of the Company,
                  subject to the Company's reimbursement policies and procedures
                  for executive officers in effect from time to time.

         4.2.2    PERQUISITES. During the Period of Employment, the Executive
                  shall be entitled to: (a) a monthly auto allowance of $750.00
                  to acquire and/or maintain a principal business vehicle, and
                  to an additional reimbursement by the Company for all
                  customary and reasonable gas, oil and incidental auto expenses
                  incurred in connection with such vehicle; and (b) Company-paid
                  parking for such vehicle at the Company's principal executive
                  offices.

4.3      VACATION AND OTHER LEAVE. During the Period of Employment, the
         Executive shall receive three (3) weeks paid vacation

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         per year; PROVIDED, that if the Period of Employment extends beyond
         the first anniversary of the Effective Date, the Executive shall
         instead be entitled to paid vacation in accordance with the
         Company's executive vacation pay policy as it may then be in effect
         if such policy results in the Executive receiving more than three
         (3) weeks paid vacation per year; PROVIDED FURTHER, that all such
         vacation shall be scheduled and taken in accordance with the
         Company's standard vacation policies. The Executive shall also be
         entitled to all other holiday and leave pay generally available to
         the Company's employees.

5.       DEATH OR DISABILITY.

5.1      DEFINITION OF DISABLED AND DISABILITY. For purposes of this Agreement,
         the terms "DISABLED" and "DISABILITY" shall mean the Executive's
         inability, because of physical or mental illness or injury, to perform
         the essential function of his customary duties pursuant to this
         Agreement, with or without reasonable accommodation, and the
         continuation of such disabled condition for a period of one hundred
         twenty (120) continuous days, or for not less than one hundred eighty
         (180) days during any continuous twenty-four (24) month period. The
         Company reserves the right, in good faith, to make the determination of
         disability under this Agreement based upon information supplied by the
         Executive and/or his medical personnel, as well as information from
         medical personnel or others selected by the Company or its insurers.

5.2      TERMINATION DUE TO DEATH OR DISABILITY. If the Executive dies or
         becomes Disabled during the Period of Employment, the Period of
         Employment and the Executive's employment shall automatically cease and
         terminate as of the date of the Executive's death or the date of
         Disability (which date shall be determined under Section 5.1 above), as
         the case may be. In the event of the termination of the Executive's
         employment due to his death or Disability, the Executive (or, in the
         event of his death, his estate) shall be entitled to receive only those
         benefits set forth in Section 8.2.1; PROVIDED that if the Executive's
         employment is terminated by reason of the Executive's Disability, he
         shall, so long as his Disability continues, remain eligible for all
         benefits provided under any long-term disability programs of the
         Company in effect at the time of such termination, subject to the terms
         and conditions of any such programs, as the same may be changed,
         modified or terminated for or with respect to employees of the Company
         generally.

6.       TERMINATION BY THE COMPANY.

6.1      TERMINATION FOR CAUSE. The Company may, by providing written notice to
         the Executive, terminate the Period of Employment and the Executive's
         employment hereunder for

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         Cause at any time. The term "CAUSE" for purposes of this Agreement
         shall mean:

         (a)      the Executive is convicted of, or has plead guilty or entered
                  a plea of nolo contendere to, a felony (under the laws of the
                  United States or any state thereof);

         (b)      fraudulent conduct by the Executive in connection with the
                  business affairs of any member of the Company Group or the
                  theft, embezzlement, or other criminal misappropriation of
                  funds by the Executive from any member of the Company Group;

         (c)      the Executive's failure to perform the duties of the Company's
                  Chief Financial Officer, after reasonable notice has been
                  provided of such non-performance and, if such failure is
                  curable, Executive has not cured such failure within a ten day
                  period following such notice;

         (d)      the Executive's failure to comply with reasonable directives
                  of the Board or the CEO which are communicated to him in
                  writing, after reasonable notice has been provided of such
                  non-performance and, if such failure is curable, Executive has
                  not cured such failure within a ten day period following such
                  notice; or

         (e)      the Executive has habitually abused any substance (such as
                  narcotics or alcohol).

         If the Executive's employment is terminated by the Company for Cause,
         the termination shall take effect on the effective date (pursuant to
         Section 17.10) of written notice of such termination to the Executive.

         In the event of the termination of the Period of Employment and the
         Executive's employment hereunder due to a termination by the Company
         for Cause, then the Executive shall be entitled to receive only those
         benefits set forth in Section 8.2.1.

6.2      TERMINATION WITHOUT CAUSE. The Company may, with or without reason,
         terminate the Period of Employment and the Executive's employment
         hereunder without Cause at any time by providing the Executive written
         notice of such termination. If the Executive's employment is terminated
         without Cause, the termination shall take effect on the effective date
         (pursuant to Section 17.10) of written notice of such termination to
         the Executive.

         In the event of the termination of the Period of Employment and the
         Executive's employment hereunder due to a termination by the Company
         without Cause (other than due to the Executive's death or Disability)
         prior to a Change in

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         Control, the Executive shall be entitled to receive those benefits
         set forth in Section 8.2.1, plus a lump sum cash payment equal to
         the amount of his Base Salary then in effect that would have
         otherwise been paid over the remainder of the Period of Employment
         then in effect had he continued in the employ of the Company
         (including any extension of the Period of Employment which has
         already occurred as of the date of termination, but not including
         any additional extension of the period of the Period of Employment).
         The Company will not terminate Executive in anticipation of a Change
         in Control (as such term is described below) and if such termination
         occurs, benefits as described in Sections 6.2(a)(b)(c) below will
         apply.

         In the event of the termination of the Period of Employment and the
         Executive's employment hereunder due to a termination by the Company
         without Cause (other than due to the Executive's death or Disability)
         upon or following a Change in Control (as such term is defined below),
         or a requirement that the Executive relocate outside the state of
         California, the Executive shall be entitled to receive:

         (a)      those benefits set forth in Section 8.2.1 hereof;

         (b)      a lump sum severance payment equal to twelve (12) times the
                  Executive's monthly Base Salary in effect immediately prior to
                  such termination; and

         (c)      All outstanding stock options granted to Executive shall
                  become fully vested.

         (d)      the Company will allow the Executive to exercise any stock
                  options granted by delivering a note to the Company on the
                  following terms and conditions:

                  (i)      The principal of the note shall not exceed the amount
                           required to be paid to the Company upon the exercise
                           of one or more of such stock options and the note
                           shall be delivered directly to the Company in
                           consideration of such exercise.

                  (ii)     The term of the note shall not exceed a period of one
                           month.

                  (iii)    The note shall provide for full recourse to the
                           Executive and shall bear interest at a rate equal to
                           the interest rate then charged to the Company by the
                           Company's primary bank lender.

                  (iv)     The note shall be secured by a pledge of the shares
                           financed thereby.

                  (v)      The terms, repayment provisions, and collateral
                           release provisions of the note and the pledge
                           securing the note shall conform with applicable rules
                           and regulations, including those of the

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                           Federal Reserve Board and under the California
                           Corporations Code, as then in effect, and shall be
                           on such other reasonable terms as the Company may
                           require.

         If a Change in Control results in a diminution of the Executive's
         senior management position, responsibilities or compensation and
         benefits as CFO, in his reporting responsibility to the CEO or in a
         relocation of his office to a location more than twenty additional
         miles from his residence, he may, within three months of such
         diminution, change in reporting responsibility or relocation, terminate
         his employment and be entitled to those benefits specified in Sections
         6.2(a)(b)(c) above.

         For purposes of this Section 6.2, "Change in Control" means any of
         the following:

         (x)      Approval by the shareholders of the Company of the dissolution
                  or liquidation of the Company;

         (y)      Consummation of a merger, consolidation, or other
                  reorganization, with or into, or the sale of all or
                  substantially all of the Company's business and/or assets as
                  an entirety to, one or more entities that are not subsidiaries
                  or other affiliates of the Company (a "Business Combination"),
                  unless (1) as a result of the Business Combination more than
                  50% of the outstanding voting power generally in the election
                  of directors of the surviving or resulting entity or a parent
                  thereof (the "Successor Entity") immediately after the
                  reorganization are, or will be, owned, directly or indirectly,
                  by holders of the Company's voting securities immediately
                  before the Business Combination; and (2) no "person" (as such
                  term is used in Sections 13(d) and 14(d) of the Securities
                  Exchange Act of 1934, as amended, excluding the Successor
                  Entity or an Excluded Person (as such term is defined below))
                  beneficially owns, directly or indirectly, more than 50% of
                  the outstanding shares or the combined voting power of the
                  outstanding voting securities of the Successor Entity, after
                  giving effect to the Business Combination, except to the
                  extent that such ownership existed prior to the Business
                  Combination; or

         (z)      Any "person" (as such term is used in Sections 13(d) and 14(d)
                  of the Securities Exchange Act of 1934, as amended, other than
                  an Excluded Person becomes the beneficial owner (as defined in
                  Rule 13d-3 under the Securities Exchange Act of 1934, as
                  amended), directly or indirectly, of securities of the
                  Corporation representing more than 50% of the combined voting
                  power of the Corporation's then outstanding securities
                  entitled to then vote generally in the election of directors
                  of the Corporation, other than as a result of

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                  (1) an acquisition directly from the Company, (2) an
                  acquisition by the Company, (3) an acquisition by any
                  employee benefit plan (or related trust) sponsored or
                  maintained by the Company or a Successor Entity, or (4) an
                  acquisition by an entity pursuant to a transaction which is
                  expressly excluded under clause (b) above.

         "Excluded Person" means (a) any person described in and satisfying the
         conditions of Rule 13d-1(b)(1) under the Securities Exchange Act of
         1934, as amended, (b) the Company, (c) an employee benefit plan (or
         related trust) sponsored or maintained by the Company or the Successor
         Entity, or (d) any person who is the beneficial owner (as defined in
         Rule 13d-3 under the Securities Exchange Act of 1934, as amended) of
         more than 10% of the outstanding shares of Common Stock on the
         Effective Date (or any affiliate, successor or related party of or to
         any such person).

7.       TERMINATION BY THE EXECUTIVE. The Executive shall have the right to
         terminate the Period of Employment and the Executive's employment
         hereunder at any time upon four (4) months prior written notice of such
         termination to the Company. Upon such a termination by the Executive,
         he shall be entitled only to those benefits set forth in Section 8.2.1.

8.       EXPIRATION OF PERIOD OF EMPLOYMENT.

8.1      BENEFITS UPON EXPIRATION OF PERIOD OF EMPLOYMENT. If either party
         elects not to extend the Period of Employment pursuant to Section 2,
         unless the Executive's employment is earlier terminated pursuant to
         Section 5, 6 or 7, termination of the Executive's employment hereunder
         shall be deemed to occur at the close of business on the day
         immediately preceding the next anniversary of the Effective Date which
         occurs at least four (4) months after delivery of the non-extension
         notice in accordance with Section 2. If the Company or the Executive
         elect not to extend the Period of Employment, upon the Executive's
         termination in accordance with the preceding sentence he will be
         entitled to only those benefits set forth in Section 8.2.1.

8.2      GENERAL TERMINATION PROVISIONS.

         8.2.1    GENERAL TERMINATION BENEFITS. In the case of any of the
                  foregoing terminations or the expiration of the Period of
                  Employment, the Executive or his estate shall be entitled to
                  (without duplication of benefits):

                  (a)      any accrued but unpaid Base Salary as of the date of
                           such termination, including unused vacation;

                  (b)      any earned but unpaid cash incentive compensation as
                           of the date of such termination;

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                  (c)      any reimbursements or allowances due but not yet paid
                           the Executive; and

                  (d)      such employee benefits described in Section 4.1 as
                           the Executive or his estate may be entitled to
                           hereunder or under the employee benefit plans,
                           programs and arrangements of the Company.

                  All amounts due the Executive in accordance with this Section
                  8.2.1 shall be paid promptly following their becoming due as
                  provided hereunder.

         8.2.2    OTHER TERMINATION PROVISIONS. In the event of any termination
                  of employment under this Agreement, the Executive shall be
                  under no obligation to seek other employment and there shall
                  be no offset against amounts due the Executive under this
                  Agreement on account of any remuneration attributable to any
                  subsequent employment that he may obtain except on account of
                  any claims the Company may have against the Executive. Any
                  amounts due under Sections 5, 6, 7 or 8 are in the nature of
                  severance payments considered to be reasonable by the Company
                  and are not in the nature of a penalty.

9.       SECTION 280G PROVISIONS.

         Notwithstanding contained in this Agreement to the contrary, to the
         extent that any payment or distribution of any type to or for the
         Executive by the Company or any of its affiliates, whether paid or
         payable or distributed or distributable pursuant to the terms of this
         Agreement or otherwise (including, without limitation, any accelerated
         vesting of stock options or restricted stock granted by the Company
         pursuant to this Agreement or otherwise) (collectively, the "TOTAL
         PAYMENTS") is or will be subject to the excise tax imposed under
         Section 4999 of the Internal Revenue Code of 1986, as amended (the
         "CODE"), then the Total Payments shall be reduced (but not below zero)
         so that the maximum amount of the Total Payments (after reduction)
         shall be one dollar ($1.00) less than the amount which would cause the
         Total Payments to be subject to the excise tax imposed by Section 4999
         of the Code. Unless the Executive shall have given prior written notice
         to the Company to effectuate a reduction in the Total Payments if such
         a reduction is required, the Company shall reduce or eliminate the
         Total Payments by first reducing or eliminating any cash severance
         benefits, then by reducing or eliminating any accelerated vesting of
         stock options, then by reducing or eliminating any accelerated vesting
         of restricted stock, then by reducing or eliminating any other
         remaining Total Payments. The preceding provisions of this Section 9
         shall take precedence over the provisions of any other plan,
         arrangement or agreement governing the Executive's rights and
         entitlements to any benefits or compensation.

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         Any determination that Total Payments to the Executive must be reduced
         or eliminated in accordance with the forgoing provisions of this
         Section 9 and the assumptions to be utilized in arriving at such
         determination, shall be made by a nationally recognized accounting firm
         or consulting firm with experience in such matters selected by the
         Company (the "ACCOUNTING FIRM"), which shall provide detailed
         supporting calculations both to the Company and the Executive within
         fifteen (15) business days after the date such calculation is requested
         by the Company or the Executive. All fees and expenses of the
         Accounting Firm shall be borne solely by the Company. If a reduction or
         elimination of Total Payments to the Executive in accordance with the
         foregoing is necessary based on the Accounting Firm's determination,
         the Accounting Firm shall furnish the Executive with a written opinion
         that failure to limit the amount of the Total Payments would result in
         the imposition of a tax under Section 4999 of the Code. Any
         determination by the Accounting Firm shall be binding upon the Company
         and the Executive. As a result of the uncertainty in the application of
         Section 4999 of the Code at the time of the initial determination by
         the Accounting Firm hereunder, it is possible that Total Payments to
         the Executive which will not have been made by the Company should have
         been made ("UNDERPAYMENT"). The Accounting Firm shall determine the
         amount of the Underpayment that has occurred and any such Underpayment
         shall be promptly paid by the Company to or for the benefit of the
         Executive. In the event that any Total Payment made to the Executive
         shall be determined by the Accounting Firm to result in the imposition
         of any tax under Section 4999 of the Code, the amount of such excess
         Total Payment shall be a loan from the Company to the Executive, and
         the Executive shall promptly reimburse the Company for the amount of
         such excess together with interest on such amount (at the same rate as
         is applied to determine the present value of payments under Section
         280G or any successor thereto), from the date the reimbursable payment
         was received by the Executive to the date the same is repaid to the
         Company.

10.      MEANS AND EFFECT OF TERMINATION.

         Any termination of the Executive's employment under this Agreement
         shall be communicated by written notice of termination from the
         terminating party to the other party. The notice of termination shall
         indicate the specific provision(s) of this Agreement relied upon in
         effecting the termination and shall set forth in reasonable detail the
         facts and circumstances alleged to provide a basis for termination, if
         any such basis is required by the applicable provision(s) of this
         Agreement.

11.      NON-COMPETITION.

         The Executive acknowledges and recognizes the highly competitive nature
         of the businesses of the Company Group, the amount of sensitive and
         confidential information

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         involved in the discharge of the Executive's position as Chief
         Financial Officer of the Company, and the harm to the Company Group
         that would result if such knowledge or expertise was disclosed or made
         available to a competitor, and accordingly agrees as follows:

         (a)      During the Period of Employment and, as a result of the
                  particular nature of the Executive's relationship with the
                  Company as its Chief Financial Officer, for the two (2) year
                  period immediately following the termination of the Period of
                  Employment, the Executive will not, directly or indirectly,
                  (i) engage in any business for the Executive's own account
                  that competes with the business of any entity within the
                  Company Group, (ii) enter the employ of, or render any
                  services to, any person engaged in any business that competes
                  with the business of any entity within the Company Group,
                  (iii) acquire a financial interest in any person engaged in
                  any business that competes with the business of any entity
                  within the Company Group, directly or indirectly, as an
                  individual, partner, shareholder, officer, director,
                  principal, agent, trustee or consultant, or (iv) interfere
                  with business relationships (whether formed before or after
                  the date of this Agreement) between the Company, any of its
                  affiliates or subsidiaries, and any customers, suppliers,
                  officers, employees, partners, members or investors of any
                  entity within the Company Group.

         (b)      Notwithstanding anything to the contrary in this Agreement,
                  the Executive may, directly or indirectly, own, solely as an
                  investment, securities of any person engaged in the business
                  of the Company or its affiliates which are publicly traded on
                  a national or regional stock exchange or on an
                  over-the-counter market if the Executive (i) is not a
                  controlling person of, or a member of a group which controls,
                  such person and (ii) does not, directly or indirectly, own
                  five percent (5%) or more of any class of securities of such
                  person.

         For purposes of this Agreement, businesses in competition with the
         Company Group shall mean (x) businesses which any entity within the
         Company Group has specific plans to conduct in the future and as to
         which the Executive is aware of such planning, and (y) other businesses
         that are in the plasma collection industry. Solely for purposes of
         clauses (a)(i), (a)(ii), and (a)(iii) of this Section 11 (but for no
         other purpose of this Section 12 or any other provision of this
         Agreement), a business that would otherwise be in competition with the
         Company Group in accordance with the preceding sentence shall not be
         deemed to be in competition with the Company Group if each of its
         places of business are

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         no closer than 50 miles to the nearest place of business of the
         Company Group.

12.      CONFIDENTIALITY.

         The Executive will not at any time (whether during or after his
         employment with the Company), other in the course of his duties
         hereunder or unless compelled by lawful process, disclose or use for
         his own benefit or purposes or the benefit or purposes of any other
         person, firm, partnership, joint venture, association, corporation or
         other business organization, entity or enterprise other than an entity
         then within the Company Group, any trade secrets, or other confidential
         data or information relating to customers, development programs, costs,
         marketing, trading, investment, sales activities, promotion, credit and
         financial data, financing methods, or plans of any entity within the
         Company Group; PROVIDED that the foregoing shall not apply to
         information which is generally known to the industry or the public
         other than as a result of the Executive's breach of this covenant. The
         Executive agrees that upon termination of his employment with the
         Company for any reason, he will return to the Company immediately all
         memoranda, books, papers, plans, information, letters and other data,
         and all copies thereof or therefrom, in any way relating to the
         business of any entity within the Company Group, except that he may
         retain personal notes, notebooks and diaries that do not contain
         confidential information of the type described in the preceding
         sentence. The Executive further agrees that he will not retain or use
         for his account at any time any trade names, trademark or other
         proprietary business designation used or owned in connection with the
         business of any entity within the Company Group.

13.      ANTISOLICITATION; NO DISPARAGEMENT.

         The Executive promises and agrees that during the Period of Employment
         and for a period of two (2) years thereafter:

         (a)      he will not influence or attempt to influence customers of any
                  entity within the Company Group (as it may now or in the
                  future be composed), either directly or indirectly, to divert
                  their business away from the Company Group to any individual,
                  partnership, firm, corporation or other entity then in
                  competition with the business of any entity within the Company
                  Group; and

         (b)      he will not make disparaging statements, whether oral or
                  written, regarding any entity within the Company Group.

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14.      SOLICITING EMPLOYEES.

         The Executive promises and agrees that for a period of one year
         following termination of his employment he will not directly or
         indirectly solicit any person who is then, or at any time within six
         months prior thereto was, an employee of an entity within the Company
         Group who earned on an annual basis $25,000 or more as an employee of
         such entity at any time during the last six months of his or her own
         employment to work for any business, individual, partnership, firm,
         corporation, or other entity then in competition with the business of
         any entity within the Company Group.

15.      COOPERATION IN LITIGATION.

         The Executive agrees that he will reasonably cooperate with the
         Company, subject to his reasonable personal and business schedules, in
         any litigation which arises out of events occurring prior to the
         termination of his employment, including but not limited to, serving as
         a witness or consultant and producing documents and information
         relevant to the case or helpful to the Company. The Company agrees to
         reimburse the Executive for all reasonable costs and expenses he incurs
         in connection with his obligations under this Section 15.

16.      INDEMNIFICATION.

         The Company agrees to indemnify the Executive to the fullest extent
         permitted by the law of the jurisdiction in which the Company is
         incorporated against claims asserted against him personally arising out
         of, or related to, the business of the Company or the Executive's
         services for the Company. The Company shall provide officers' liability
         insurance coverage to the Executive consistent with the levels of
         coverage that it provides generally to its other executive officers
         from time to time.

17.      GENERAL.

17.1     ASSIGNMENT. This Agreement is personal in its nature and neither of the
         parties hereto shall, without the consent of the other, assign or
         transfer this Agreement or any rights or obligations hereunder;
         PROVIDED, HOWEVER, that, in the event of a merger, consolidation, or
         transfer or sale of all or substantially all of the assets of the
         Company with or to any other individual(s) or entity, this Agreement
         shall, subject to the provisions hereof, be binding upon and inure to
         the benefit of such successor and such successor shall discharge and
         perform all the promises, covenants, duties, and obligations of the
         Company hereunder.

17.2     GOVERNING LAW. This Agreement and the legal relations hereby created
         between the parties hereto shall be governed by and construed under and
         in accordance with the internal

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<PAGE>

         laws of the State of California, without regard to conflicts of laws
         principles thereof.

         The Executive and the Company agree (a) that his or its legal counsel
         participated in the preparation of this Agreement and/or he or it has
         had ample opportunity to have his or its legal counsel fully examine
         this Agreement, and (b) that the rule of construction that ambiguities
         are to be resolved against the drafting party shall not be employed in
         the interpretation of this Agreement to the favor of either party
         hereto against the other.

17.3.    ENTIRE AGREEMENT. This Agreement embodies the entire agreement of the
         parties hereto respecting the matters within its scope. This Agreement
         supersedes all prior agreements of the parties hereto on the subject
         matter hereof. Any prior negotiations, correspondence, agreements,
         proposals or understandings relating to the subject matter hereof shall
         he deemed to be merged into this Agreement and to the extent
         inconsistent herewith, such negotiations, correspondence, agreements,
         proposals, or understandings shall be deemed to be of no force or
         effect. There are no representations, warranties, or agreements,
         whether express or implied, or oral or written, with respect to the
         subject matter hereof, except as set forth herein.

17.4     MODIFICATIONS. This Agreement shall not be modified by any oral
         agreement, either express or implied, and all modifications hereof
         shall be in writing and signed by the parties hereto.

17.5     WAIVER. Failure to insist upon strict compliance with any of the terms,
         covenants, or conditions hereof shall not be deemed a waiver of such
         term, covenant, or condition, nor shall any waiver or relinquishment
         of, or failure to insist upon strict compliance with, any right or
         power hereunder at any one or more times be deemed a waiver or
         relinquishment of such right or power at any other time or times.

17.6     NUMBER AND GENDER. Where the context requires, the singular shall
         include the plural, the plural shall include the singular, and any
         gender shall include all other genders.

17.7     SECTION HEADINGS. The section headings in this Agreement are for the
         purpose of convenience only and shall not limit or otherwise affect any
         of the terms hereof.

17.8     RESTRICTIONS ON THE EXECUTIVE. Each of the restrictions on the
         Executive set forth in Section 11, 12, 13, 14 and/or 15 shall be
         construed as an independent covenant, and the existence of any claim or
         cause of action against the Company, whether predicated upon this
         Agreement or otherwise, shall not constitute a defense to the
         enforcement by the Company of any of such restrictions. The Executive
         agrees that such restrictions are reasonable (including,

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<PAGE>

         without limitation, reasonable as to time, geographical area and
         scope).

17.9     SEVERABILITY. In the event that a court of competent jurisdiction
         determines that any portion of this Agreement is in violation of any
         statute or public policy, then only the portions of this Agreement
         which violate such statute or public policy shall be stricken, and all
         portions of this Agreement which do not violate any statute or public
         policy shall continue in full force and effect. Furthermore, any court
         order striking any portion of this Agreement shall modify the stricken
         terms as narrowly as possible to give as much effect as possible to the
         intentions of the parties under this Agreement.

17.10    NOTICES. All notices under this Agreement shall be in writing and shall
         be either personally delivered or mailed postage prepaid, by certified
         United States mail, return receipt requested:

         (a)      if to the Company, at the address of the Company's principal
                  executive offices to the attention of the Chief Executive
                  Officer; or

         (b)      if to the Executive, at the address of the Executive's
                  principal residence as last reflected on the Company's
                  records.

         Either party may change its address set forth above by written notice
         given to the other party in accordance with the foregoing. Any notice
         shall be effective when personally delivered, or five (5) business days
         after being mailed in accordance with the foregoing.

17.11    COUNTERPARTS. This Agreement may be executed in any number of
         counterparts, each of which shall be deemed an original and all of
         which together shall constitute one and the same instrument.

17.12    WITHHOLDING TAXES. The Company may withhold from any amounts payable
         under this Agreement such federal, state and local income, employment,
         or other taxes as may be required to be withheld pursuant to any
         applicable law or regulation.

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         IN WITNESS WHEREOF, the Company and the Executive have executed this
Employment Agreement as of the date first above written.

                                      THE COMPANY
                                      SeraCare, Inc.,
                                      a California corporation


                                      By: /s/ Barry D. Plost
                                          --------------------------------
                                              Barry D. Plost
                                              Chief Executive Officer


                                      THE EXECUTIVE

                                      /s/ James Linesch
                                      -------------------------------
                                      James Linesch



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