LJL BIOSYSTEMS, INC.


                          REGISTRATION RIGHTS AGREEMENT


                                 JANUARY 27, 1999



                               LJL BIOSYSTEMS, INC.

                          REGISTRATION RIGHTS AGREEMENT

     This Registration Rights Agreement (the "AGREEMENT") is made as of the 
27th day of January, 1999, by and among LJL BioSystems, Inc., a Delaware 
corporation (the "COMPANY") and the investors listed on ATTACHMENT A hereto, 
each of which is herein referred to as an "INVESTOR."

                                   RECITALS

     The Company and the Investors have entered into a Common Stock Purchase 
Agreement (the "PURCHASE AGREEMENT") of even date herewith pursuant to which 
the Company has agreed to sell to the Investors and the Investors have agreed 
to purchase from the Company shares of the Company's Common Stock.

     ALL TERMS NOT OTHERWISE DEFINED HEREIN SHALL HAVE THE MEANINGS ASCRIBED 
IN THE PURCHASE AGREEMENT.

     A condition to the Investors' obligations under the Purchase Agreement 
is that the Company and the Investors enter into this Agreement in order to 
provide the Investors with certain rights to register the Securities acquired 
by the Investors subject to the Purchase Agreement.  The Company and the 
Investors each desire to induce the Investors to purchase the Securities 
pursuant to the Purchase Agreement by agreeing to the terms and conditions 
set forth herein.

                                  AGREEMENT

     The parties hereby agree as follows:

          1.   REGISTRATION RIGHTS. The Company and the Investors covenant 
and agree as follows:

               1.1  DEFINITIONS. For purposes of this Section 1 (terms 
defined in the singular shall apply to the plural form and vice-versa):

                    (a)  The terms "REGISTER," "REGISTERED," and 
"REGISTRATION" refer to a registration effected by preparing and filing a 
registration statement or similar document in compliance with the Securities 
Act of 1933, as amended (the "ACT"), and the declaration or ordering of 
effectiveness of such registration statement or document;

                    (b)  The term "REGISTRABLE SECURITIES" means (i) the 
shares of Common Stock issued or sold in connection with the Purchase 
Agreement (such shares of Common Stock are collectively referred to 
hereinafter as the "SHARES" or "STOCK"), and (ii) any other shares of Common 
Stock of the Company issued as (or issuable upon the conversion or exercise 
of any warrant, right or other security which is issued as) a dividend or 
other distribution with respect to, or in exchange for or in replacement of, 
the Stock, PROVIDED, that the foregoing 



definition shall exclude in all cases any Registrable Securities sold by a 
person in a transaction in which his or her rights under this Agreement are 
not assigned.   Notwithstanding the foregoing, Common Stock or other 
securities shall only be treated as Registrable Securities if and so long as 
they have not (A) been sold to or through a broker or dealer or underwriter 
in a public distribution or a public securities transaction, or (B) been sold 
in a transaction exempt from the registration and prospectus delivery 
requirements of the Act under Section 4(1) thereof so that all transfer 
restrictions, and restrictive legends with respect thereto, if any, are 
removed upon the consummation of such sale or (C) with regard to any 
individual Holder, become eligible for sale in any three month period 
pursuant to Rule 144;

                    (c)  The number of shares of "REGISTRABLE SECURITIES THEN 
OUTSTANDING" shall be determined by the number of shares of Common Stock 
outstanding which are, and the number of shares of Common Stock issuable 
pursuant to then exercisable or convertible securities which are, Registrable 
Securities;

                    (d)  The term "HOLDER" means any person owning or having 
the right to acquire Registrable Securities or any assignee thereof in 
accordance with this Agreement;

                    (e)  The term "FORM S-3" means such form under the Act as 
in effect on the date hereof or any successor form under the Act; and

                    (f)  The term "SEC" means the Securities and Exchange 
Commission.

               1.2  FORM S-3 REGISTRATION. Subject to the terms and 
conditions of this Agreement, on or before the date that is six (6) months 
following the Closing (the "S-3 DATE"), the Company will file with the SEC a 
registration statement on Form S-3 and will use its best efforts to effect 
such registration and any related qualification or compliance with respect to 
all Registrable Securities owned by the Holders as soon as practicable 
thereafter.  If the Company does not file with the SEC a registration 
statement on Form S-3 by the date that is 30 days after the S-3 Date (the 
"S-3 Filing Deadline"), the Company agrees to pay the Purchasers, as 
liquidated damages, an amount equal to Two Hundred Fifty Thousand Dollars 
($250,000) on the day immediately after the S-3 Filing Deadline, provided 
however, that notwithstanding the above, the Company shall not pay any such 
damages if the Company defers filing a registration statement on Form S-3 
pursuant to subsection 1.2(b)(i) or subsection 1.2(b)(ii) below.  
Accordingly, the Company will:

                    (a)  promptly give written notice of the registration, 
and any related qualification or compliance, to all Holders;

                    (b)  as soon as practicable, effect such registration and 
all such qualifications and compliances as may be necessary and as would 
permit or facilitate the sale and distribution of all of the Holders' 
Registrable Securities; provided, however, that the Company shall not be 
obligated to effect any such registration, qualification or compliance, 
pursuant to this Section 1.2 if (i) the Company shall furnish to the Holders 
a certificate signed by the President of the Company stating that in the good 
faith judgment of the Board of Directors of the Company, it 

                                       2


would be seriously detrimental to the Company and its stockholders for such 
Form S-3 Registration to be effected at such time, in which event the Company 
shall have the right to defer the filing of the Form S-3 registration 
statement for a reasonable period of time, which shall not exceed thirty (30) 
days after the S-3 Filing Deadline, under this Section 1.2 or (ii) if Form 
S-3 is not available for such offering by the Holder(s), provided, however, 
that if Form S-3 is not available, Company shall file the Form S-3 
registration statement once it is available; and

                    (c)  any and all expenses incurred in connection with a 
registration requested pursuant to this Section 1.2 shall be borne by the 
Company, including all registration, filing, qualification, printers' and 
accounting fees but excluding any underwriters' discounts or commissions and 
any fees and disbursements of any counsel for the selling Holders (such fees 
or discounts, if any, to be borne pro rata by the Holders participating in 
the registration).

               1.3  OBLIGATIONS OF THE COMPANY. Whenever required under this 
Section 1 to effect the registration of any Registrable Securities, the 
Company shall, as expeditiously as reasonably possible:

                    (a)  Prepare and file with the SEC a registration 
statement with respect to such Registrable Securities and use its best 
efforts to cause such registration statement to become effective and to keep 
such registration statement effective for a period of three (3) years after 
the date on which the registration statement is declared effective or such 
shorter period:  (i) when all of the Registrable Securities covered by the 
registration statement are sold; or (ii) when Rule 144(k) is available to 
each of the Investors.

                    (b)  Prepare and file with the SEC such amendments and 
supplements to such registration statement and the prospectus used in 
connection with such registration statement as may be necessary to comply 
with the provisions of the Act with respect to the disposition of all 
securities covered by such registration statement.

                    (c)  Furnish to the Holders such numbers of copies of a 
prospectus, including a preliminary prospectus, in conformity with the 
requirements of the Act, and such other documents as they may reasonably 
request in order to facilitate the disposition of Registrable Securities 
owned by them.

                    (d)  Use its best efforts to register and qualify the 
securities covered by such registration statement under such other securities 
or blue sky laws of such jurisdictions as shall be reasonably requested by 
the Holders, provided that the Company shall not be required in connection 
therewith or as a condition thereto to qualify to do business or to file a 
general consent to service of process in any such states or jurisdictions.

                    (e)  Notify each Holder of Registrable Securities covered 
by such registration statement at any time when a prospectus relating thereto 
is required to be delivered under the Act of the happening of any event as a 
result of which the prospectus included in such registration statement, as 
then in effect, includes an untrue statement of a material fact or omits to 
state a material fact required to be stated therein or necessary to make 

                                       3


the statements therein not misleading in the light of the circumstances then 
existing.  In such circumstance, the Company will use reasonable commercial 
efforts to promptly update such prospectus to correct such untrue statement 
or disclose the necessary material facts within the period of time the 
Company may delay sales under Section 1.4(a)(iii) below.
                    

               1.4  RESTRICTIONS ON AND PROCEDURE FOR SALES PURSUANT TO A
                    REGISTRATION STATEMENT.

                    (a)  Each Holder agrees to the following:

                         (i)  NOTICE TO COMPANY.  If any Holder shall propose 
to sell any Shares, the Holder shall notify the Company of its intent to do 
so on or before one (1) business day prior to the date of such sale (the 
"Notice of Sale"), and the provision of the Notice of Sale to the Company 
shall conclusively be deemed to establish an agreement by such Holder to 
comply with the registration provisions herein described.  The Notice of Sale 
shall be deemed to constitute a representation that any information 
previously supplied by such Holder is accurate as of the date of such Notice 
of Sale.

                         (ii) NOTICE OF SALE.  The Notice of Sale in 
substantially the form attached as ATTACHMENT B shall be given in accordance 
with the provisions of Section 2.5 hereof.  However, the Holder may give the 
Notice of Sale orally by telephoning the current Chief Financial Officer at 
the Company at (408) 448-0542.  An oral Notice of Sale shall be deemed to 
have been received only at such time as the Selling Holder speaks directly 
with the current Chief Financial Officer.  In addition, an oral Notice of 
Sale shall only be deemed effective if it is followed by a written Notice of 
Sale received by the Company by personal delivery or facsimile within 
twenty-four (24) hours after giving the oral Notice of Sale.

                        (iii) DELAY OF SALE.  The Company may refuse to 
permit the Holder to resell any Shares for a period of time not to exceed 
forty five (45) days; provided, however, that in order to exercise this 
right, the Company must deliver a certificate in writing to the Holder to the 
effect that the registration statement in its then current form contains an 
untrue statement of material fact or omits to state a material fact necessary 
in order to make the statements made therein, in light of the circumstances 
under which they were made, not misleading.  During any suspension period as 
contemplated by this Section 1.4 (a)(iii), of which there shall be no more 
than three (3) in any twelve (12) month period, the Company will not allow 
any of its officers or directors to buy or sell shares of the Company's 
securities.

                    (b)  REPRESENTATIONS OF HOLDERS.  Each Holder hereby 
represents to and covenants with the Company that, during the period in which 
any registration statement effected pursuant to Section 1.2 remains 
effective, such Holder will:

                         (i)   not engage in any stabilization activity in 
connection with any of the Company's securities;

                                       4


                         (ii)  cause to be furnished to any purchaser of the 
Shares and to the broker-dealer,  if any, through whom Shares may be offered, 
a copy of the Prospectus; and

                         (iii) not bid for or purchase any securities of the 
Company or any rights to acquire the Company's securities, or attempt to 
induce any person to purchase any of the Company's securities or any rights 
to acquire the Company's securities, in each case, other than as permitted 
under the Securities Exchange Act of 1934, as amended ("Exchange Act").

                    (c)  INFORMATION FOR USE IN REGISTRATION STATEMENT.  Each 
Holder represents and warrants to the Company that such Holder has completed 
the information requested by the Selling Holder's Questionnaire attached as 
ATTACHMENT C hereto (the "Questionnaire"), and further represents and 
warrants to the Company that all information provided by such Holder in the 
Questionnaire is true, accurate and complete.  Each Holder understands that 
the written information in the Questionnaire and all written representations 
made in this Agreement are being provided to the Company specifically for use 
in, or in connection with, the registration statement and the Prospectus, and 
has executed this Agreement with such knowledge.

               1.5  FURNISH INFORMATION.  It shall be a condition precedent 
to the obligations of the Company to take any action pursuant to this Section 
1 with respect to the Registrable Securities of any selling Holder that such 
Holder shall furnish to the Company such information regarding itself, the 
Registrable Securities held by it, and the intended method of disposition of 
such securities as shall be required to effect the registration of such 
Holder's Registrable Securities.

               1.6  DELAY OF REGISTRATION. No Holder shall have any right to 
obtain or seek an injunction restraining or otherwise delaying any such 
registration as the result of any dispute that might arise with respect to 
the interpretation or implementation of this Section 1.

               1.7  INDEMNIFICATION. In the event any Registrable Securities 
are included in a registration statement under this Section 1:

                    (a)  To the extent permitted by law, the Company will 
indemnify and hold harmless each Holder, any underwriter (as defined in the 
Act) for such Holder and each person, if any, who controls such Holder or 
underwriter within the meaning of the Act or the Exchange Act, against any 
losses, claims, damages, or liabilities (joint or several) to which they may 
become subject under the Act, the Exchange Act or other federal or state law, 
insofar as such losses, claims, damages, or liabilities (or actions in 
respect thereof) arise out of or are based upon any of the following 
statements, omissions or violations (collectively a "VIOLATION"):  (i) any 
untrue statement or alleged untrue statement of a material fact contained in 
such registration statement, including any preliminary prospectus or final 
prospectus contained therein or any amendments or supplements thereto, (ii) 
the omission or alleged omission to state therein a material fact required to 
be stated therein, or necessary to make the statements therein not 
misleading, or (iii) any violation or alleged violation by the Company of the 
Act, the 

                                       5


Exchange Act, any state securities law or any rule or regulation promulgated 
under the Act, the Exchange Act or any state securities law; and the Company 
will pay to each such Holder, underwriter or controlling person, as incurred, 
any legal or other expenses reasonably incurred by them in connection with 
investigating or defending any such loss, claim, damage, liability, or 
action; provided, however, that the indemnity agreement contained in this 
subsection 1.7(a) shall not apply to amounts paid in settlement of any such 
loss, claim, damage, liability, or action if such settlement is effected 
without the consent of the Company (which consent shall not be unreasonably 
withheld), nor shall the Company be liable in any such case for any such 
loss, claim, damage, liability, or action to the extent that it arises out of 
or is based upon a Violation which occurs in reliance upon and in conformity 
with written information furnished expressly for use in connection with such 
registration by any such Holder, underwriter or controlling person.

                    (b)  To the extent permitted by law, each selling Holder 
will indemnify and hold harmless the Company, each of its directors, each of 
its officers who has signed the registration statement, each person, if any, 
who controls the Company within the meaning of the Act, any underwriter, any 
other Holder selling securities in such registration statement and any 
controlling person of any such underwriter or other Holder, against any 
losses, claims, damages, or liabilities (joint or several) to which any of 
the foregoing persons may become subject, under the Act, the Exchange Act or 
other federal or state law, insofar as such losses, claims, damages, or 
liabilities (or actions in respect thereto) arise out of or are based upon 
any Violation, in each case to the extent (and only to the extent) that such 
Violation occurs in reliance upon and in conformity with written information 
furnished by such Holder expressly for use in connection with such 
registration; and each such Holder will pay, as incurred, any legal or other 
expenses reasonably incurred by any person intended to be indemnified 
pursuant to this subsection 1.7(b), in connection with investigating or 
defending any such loss, claim, damage, liability, or action; provided, 
however, that the indemnity agreement contained in this subsection 1.7(b) 
shall not apply to amounts paid in settlement of any such loss, claim, 
damage, liability or action if such settlement is effected without the 
consent of the Holder, which consent shall not be unreasonably withheld; 
provided, that, in no event shall any indemnity under this subsection 1.7(b) 
exceed the net proceeds from the offering received by such Holder, except in 
the case of willful fraud by such Holder.

                    (c)  Promptly after receipt by an indemnified party under 
this Section 1.7 of notice of the commencement of any action (including any 
governmental action), such indemnified party will, if a claim in respect 
thereof is to be made against any indemnifying party under this Section 1.7, 
deliver to the indemnifying party a written notice of the commencement 
thereof and the indemnifying party shall have the right to participate in, 
and, to the extent the indemnifying party so desires, jointly with any other 
indemnifying party similarly noticed, to assume the defense thereof with 
counsel mutually satisfactory to the parties; provided, however, that an 
indemnified party (together with all other indemnified parties which may be 
represented without conflict by one counsel) shall have the right to retain 
one separate counsel, with the reasonable fees and expenses to be paid by the 
indemnifying party, if representation of such indemnified party by the 
counsel retained by the indemnifying party would be inappropriate due to 
actual or potential differing interests between such indemnified party and 
any other party represented by such counsel in such proceeding.  The failure 
to deliver written notice to the 

                                      6


indemnifying party within a reasonable time of the commencement of any such 
action, if prejudicial to its ability to defend such action, shall relieve 
such indemnifying party of any liability to the indemnified party under this 
Section 1.7, but the omission so to deliver written notice to the 
indemnifying party will not relieve it of any liability that it may have to 
any indemnified party otherwise than under this Section 1.7.

                    (d)  If the indemnification provided for in this Section 
1.7 is held by a court of competent jurisdiction to be unavailable to an 
indemnified party with respect to any loss, liability, claim, damage, or 
expense referred to therein, then the indemnifying party, in lieu of 
indemnifying such indemnified party hereunder, shall contribute to the amount 
paid or payable by such indemnified party as a result of such loss, 
liability, claim, damage, or expense in such proportion as is appropriate to 
reflect the relative fault of the indemnifying party on the one hand and of 
the indemnified party on the other in connection with the statements or 
omissions that resulted in such loss, liability, claim, damage, or expense as 
well as any other relevant equitable considerations; provided, that, in no 
event shall any contribution by a Holder under this Subsection 1.7(d) exceed 
the net proceeds from the offering received by such Holder, except in the 
case of willful fraud by such Holder.  The relative fault of the indemnifying 
party and of the indemnified party shall be determined by reference to, among 
other things, whether the untrue or alleged untrue statement of a material 
fact or the omission to state a material fact relates to information supplied 
by the indemnifying party or by the indemnified party and the parties' 
relative intent, knowledge, access to information, and opportunity to correct 
or prevent such statement or omission.

                    (e)  The obligations of the Company and Holders under 
this Section 1.7 shall survive the completion of any offering of Registrable 
Securities in a registration statement under this Section 1.

               1.8  REPORTS UNDER SECURITIES EXCHANGE ACT OF 1934. With a 
view to making available to the Holders the benefits of Rule 144 and any 
other rule or regulation of the SEC that may at any time permit a Holder to 
sell securities of the Company to the public without registration or pursuant 
to a registration on Form S-3, the Company agrees to:

                    (a)  make and keep public information available, as those 
terms are understood and defined in Rule 144, so long as the Company remains 
subject to the periodic reporting requirements under Sections 13 or 15(d) of 
the Exchange Act;

                    (b)  take such action, including the voluntary 
registration of its Common Stock under Section 12 of the Exchange Act, as is 
necessary to enable the Holders to utilize Form S-3 for the sale of their 
Registrable Securities, such action to be taken as soon as practicable after 
the end of the fiscal year in which the first registration statement filed by 
the Company for the offering of its securities to the general public is 
declared effective;

                    (c)  file with the SEC in a timely manner all reports and 
other documents required of the Company under the Act and the Exchange Act; 
and

                                      7


                    (d)  furnish to any Holder, so long as the Holder owns 
any Registrable Securities, forthwith upon request (i) a written statement by 
the Company that it has complied with the reporting requirements of the 
Exchange Act and the rules and regulations promulgated thereunder, or that it 
qualifies as a registrant whose securities may be resold pursuant to Form 
S-3, (ii) a copy of the most recent annual or quarterly report of the Company 
and such other reports and documents so filed by the Company, and (iii) such 
other information as may be reasonably requested in availing any Holder of 
any rule or regulation of the SEC which permits the selling of any such 
securities without registration or pursuant to such form.

          1.9  ASSIGNMENT OF REGISTRATION RIGHTS. The rights to cause the 
Company to register Registrable Securities pursuant to this Section 1 may be 
assigned (but only with all related obligations) by a Holder to a transferee 
or assignee of at least 150,000 shares of such securities, provided the 
Company is, within a reasonable time after such transfer, furnished with 
written notice of the name and address of such transferee or assignee and the 
securities with respect to which such registration rights are being assigned, 
which information shall amend Attachment A hereto; and provided, further, 
that such assignment shall be effective only if immediately following such 
transfer the further disposition of such securities by the transferee or 
assignee is restricted under the Act.  For the purposes of determining the 
number of shares of Registrable Securities held by a transferee or assignee, 
the holdings of transferees and assignees of a partnership who are partners 
or retired partners of such partnership (including spouses and ancestors, 
lineal descendants and siblings of such partners or spouses who acquire 
Registrable Securities by gift, will or intestate succession) shall be 
aggregated together and with the partnership; provided that all assignees and 
transferees who would not qualify individually for assignment of registration 
rights shall have a single attorney-in-fact for the purpose of exercising any 
rights, receiving notices or taking any action under Section 1.

          2.   MISCELLANEOUS.

               2.1  SUCCESSORS AND ASSIGNS. Except as otherwise provided 
herein, the terms and conditions of this Agreement shall inure to the benefit 
of and be binding upon the respective successors and assigns of the parties.  
Nothing in this Agreement, express or implied, is intended to confer upon any 
party other than the parties hereto or their respective successors and 
assigns any rights, remedies, obligations, or liabilities under or by reason 
of this Agreement, except as expressly provided in this Agreement.

               2.2  GOVERNING LAW. This Agreement and all acts and 
transactions pursuant hereto shall be governed, construed and interpreted in 
accordance with the laws of the State of California, without giving effect to 
principles of conflicts of laws.

               2.3  COUNTERPARTS. This Agreement may be executed in two (2) 
or more counterparts, each of which shall be deemed an original, but all of 
which together shall constitute one and the same instrument.

               2.4  TITLES AND SUBTITLES. The titles and subtitles used in 
this Agreement are used for convenience only and are not to be considered in 
construing or interpreting this Agreement.

                                      8


               2.5  NOTICES. Unless otherwise provided herein, any notice 
required or permitted by this Agreement shall be in writing and shall be 
deemed sufficient upon delivery, when delivered personally or by overnight 
courier and addressed to a Holder to be notified at such party's address as 
set forth on ATTACHMENT A hereto or to the Company at its address on its 
signature page hereto, or as subsequently modified by written notice. In the 
event that any date provided for in this Agreement falls on a Saturday, 
Sunday or legal holiday, such date shall be deemed extended to the next 
business day. Notwithstanding the foregoing, any notice delivered pursuant to 
Section 1.3(e) or Section 1.4 hereto must be made by personal delivery or 
confirmed facsimile transmission.

               2.6  EXPENSES. If any action at law or in equity is necessary 
to enforce or interpret the terms of this Agreement, the prevailing party 
shall be entitled to reasonable attorneys' fees, costs and necessary 
disbursements in addition to any other relief to which such party may be 
entitled.

               2.7  AMENDMENTS AND WAIVERS. Any term of this Agreement may be 
amended and the observance of any term of this Agreement may be waived 
(either generally or in a particular instance and either retroactively or 
prospectively), only with the written consent of the Company and the holders 
of a majority of the Registrable Securities then outstanding.  Any amendment 
or waiver effected in accordance with this paragraph shall be binding upon 
each holder of any Registrable Securities then outstanding, each future 
holder of all such Registrable Securities, and the Company.

               2.8  SEVERABILITY.  If one or more provisions of this 
Agreement are held to be unenforceable under applicable law, the parties 
agree to renegotiate such provision in good faith.  In the event that the 
parties cannot reach a mutually agreeable and enforceable replacement for 
such provision, then (x) such provision shall be excluded from this 
Agreement, (y) the balance of the Agreement shall be interpreted as if such 
provision were so excluded and (z) the balance of the Agreement shall be 
enforceable in accordance with its terms.

               2.9  ENTIRE AGREEMENT.  This Agreement, and the documents 
referred to herein (with the exception of the registration statement) 
constitute the entire agreement between the parties hereto pertaining to the 
subject matter hereof, and any and all other written or oral agreements 
existing between the parties hereto are expressly canceled.
               
                                       
                            [SIGNATURE PAGES FOLLOW]

                                      9


     The parties have executed this Registration Rights Agreement as of the 
date first written above.

                                        COMPANY:

                                        LJL BIOSYSTEMS, INC.


                                        By: /s/ Lev J. Leytes
                                            --------------------------------
                                            Name:    Lev J. Leytes
                                                     -----------------------
                                            Title:   President
                                                     -----------------------
                                            Address: 405 Tasman Drive
                                                     -----------------------
                                                     Sunnyvale, CA  94089
                                                     -----------------------




     The parties have executed this Registration Rights Agreement as of the 
date first written above.

                                        THE BAY CITY CAPITAL FUND I, L.P.

                                        By:  BAY CITY CAPITAL MANAGEMENT LLC
                                        Its: General Partner


                                        By:  /s/ Roger H. Salquist
                                            --------------------------------
                                            Name:    Roger H. Salquist
                                                     -----------------------
                                            Title:   Managing Partner
                                                     -----------------------




     The parties have executed this Registration Rights Agreement as of the 
date first written above.

                                        SKYLINE VENTURE PARTNERS, L.P.


                                        By:  Skyline Venture Management LLC
                                        Its: General Partner


                                        By:  /s/ John Freund
                                            --------------------------------
                                            John Freund
                                            Managing Director

                                      2



     The parties have executed this Registration Rights Agreement as of the 
date first written above.

                                        THE KAUFMANN FUND, INC.


                                        By:  /s/ Hans P. Utsch
                                            --------------------------------
                                            Hans P. Utsch
                                            President

                                      3



                                 ATTACHMENT A

                                  INVESTORS


                                                       No. of Shares
Name/Address                                           of Common Stock
- ------------                                           ---------------
                                                    
The Bay City Capital Fund I, L.P.                          857,143
750 Battery Street, Suite 600
San Francisco, CA  94111

The Kaufmann Fund, Inc.                                    857,143
140 E. 45th Street, 43rd Floor
New York, NY  10017

Skyline Venture Partners, L.P.                             285,714
525 University Avenue, Suite 701
Palo Alto, CA  94301




                                       
                                  ATTACHMENT B

                              LJL BIOSYSTEMS, INC.

                                 NOTICE OF SALE



     Pursuant to the Registration Rights Agreement dated as of __________, 
1999 among LJL BioSystems, Inc. (the "Company"), the undersigned and certain 
stockholders of the Company, the undersigned hereby gives notice to the 
Company of the undersigned's intent to sell _______ shares of the Company's 
Common Stock registered pursuant to the registration statement on 
(File No.__________).



Dated:   ______________, 199__          By:___________________________________
                                                        (signature)


                                        Name:_________________________________
                                                          (print)


                                        Title:________________________________
                                                      (if applicable)











     [NOTE: THIS NOTICE OF SALE MUST BE COMPLETED AND DELIVERED (VIA PERSONAL
     DELIVERY OR FACSIMILE) TO THE CHIEF FINANCIAL OFFICER OF THE COMPANY ON OR
     BEFORE ONE (1) BUSINESS DAY BEFORE THE DATE OF SALE OF THE SHARES OF THE
     COMPANY'S COMMON STOCK REGISTERED PURSUANT TO THE REGISTRATION STATEMENT.]


                                       

                                  ATTACHMENT C

                              LJL BIOSYSTEMS, INC.

                      SELLING STOCKHOLDER'S QUESTIONNAIRE


     In connection with the LJL BioSystems, Inc. (the "Company") Registration 
Statement (File No.__________) registering certain shares of the Company's 
Common Stock, the undersigned represents and warrants that the information 
set forth below is true, accurate and complete:

     1.  As of the date hereof, the undersigned beneficially owns ______ 
shares of the Company's Common Stock.

     2.  Except as described below, the undersigned has not had a material 
relationship with the Company or any of its predecessors or affiliates within 
the last three years.  

     The term "material relationship" has not been defined by the Securities 
and Exchange Commission (the "SEC").  However, the SEC has indicated that it 
will probably construe as a "material relationship" any relationship which 
tends to prevent arms length bargaining in dealings with a company, whether 
arising from a close business connection or family relationship, a 
relationship of control or otherwise.  It seems prudent, therefore, to 
consider that the undersigned would have such a relationship, for example, 
with any organization of which the undersigned is an officer, director, 
trustee or partner or in which the undersigned owns, directly or indirectly, 
ten percent (10%) or more of the outstanding voting stock, or in which the 
undersigned has some other substantial interest, and with any person or 
organization with whom the undersigned has, or with whom any relative or 
spouse (or any other person or organization as to which the undersigned has 
any of the foregoing other relationships) has, a contractual relationship.

     If applicable, please describe the material relationship with the Company:
_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________
 
                                        Holder

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                                        Name: _________________________________
                                        Title:_________________________________