CONTROL NUMBER                   BIOTIME, INC.     SUBSCRIPTION CERTIFICATE FOR

   
                   SUBSCRIPTION CERTIFICATE FOR COMMON SHARES
                  VOID IF NOT EXERCISED AT OR BEFORE 5:00 P.M.
             (NEW YORK TIME) ON ______, 1999, THE EXPIRATION DATE.        RIGHTS
                 THIS SUBSCRIPTION CERTIFICATE IS TRANSFERRABLE
                         AND MAY BE COMBINED OR DIVIDED
Expiration Date               (BUT ONLY INTO SUBSCRIPTION     SUBSCRIPTION PRICE
______, 1999   CERTIFICATES EVIDENCING A WHOLE NUMBER OF RIGHTS)    U.S. $______
                    AT THE OFFICE OF THE SUBSCRIPTION AGENT            PER SHARE

                                                               CUSIP
                                                         09066L 12 1
    

THIS SUBSCRIPTION CERTIFICATE MAY BE USED TO SUBSCRIBE FOR
COMMON SHARES OR MAY BE ASSIGNED OR SOLD. FULL INSTRUCTIONS
APPEAR ON THE BACK OF THIS SUBSCRIPTION CERTIFICATE.

REGISTERED OWNER:

   
The registered owner of this Subscription Certificate, named above, or assignee,
is  entitled  to the number of Rights to  subscribe  for Common  Shares,  no par
value,  of BioTime,  Inc. shown above, in the ratio of one Common Share for each
20 Rights  held,  and upon the terms  and  conditions  and at the price for each
Common Share specified in the Prospectus dated ______, 1999.


If you  exercise  fewer than all the  Rights  represented  by this  Subscription
Certificate,  the subscription  agent will issue a new Subscription  Certificate
representing  the  balance  of  the  unexercised   Rights,   provided  that  the
subscription   agent  has  received   your   properly   completed  and  executed
Subscription  Certificate  and  payment  prior to 5:00 p.m.,  New York time,  on
______, 1999. No new Subscription Certificate will be issued after that date.


IMPORTANT: Complete appropriate form on reverse

DATE:    , 1999
                                  BIOTIME, INC.
    

- --------------------------------------------------------------------------------
                                    SECRETARY



   
- --------------------------------------------------------------------------------
                            CHIEF EXECUTIVE OFFICER
    


Countersigned: American Stock Transfer & Trust Company (New York, N.Y.)
                Subscription Agent

         By: ___________________________________________
             Authorized Signature


                                   EXHIBIT 4.4


       

                                        





                                                   Expiration Date: ______, 1999


                   PLEASE COMPLETE ALL APPLICABLE INFORMATION
                                                                               

     By Mail:                                 By Hand:                                   By Overnight Courier:      
 To: America Stock                        To: America Stock                          To: American Stock             
     Transfer & Trust Company                 Transfer & Trust Company                   Transfer & Trust Company   
     40 Wall Street                           40 Wall Street, 46th Floor                 40 Wall Street, 46th Floor 
     New York, New York 10005                 New York, New York 10005                   New York, New York 10005   
                                                                        

SECTION  1: TO SUBSCRIBE:  I hereby irrevocably  subscribe for the dollar amount
         of common shares indicated as the total of A and B below upon the terms
         and conditions  specified in the Prospectus related hereto,  receipt of
         which is acknowledged.

   
         TO SELL: If I have checked  either the box on line C or the box on line
         D, I authorize the sale of Rights by the  subscription  agent according
         to the  procedures  described  in the  Prospectus.  The  check  for the
         proceeds of sale will be mailed to the address of record.
    

Please check [X] below:

[ ] A. Subscription                    divided by 20 =              .000 x $                   = $
                    ------------------                 ------------------  --------------------  ----------------
                    (Rights Exercised)                 (Shares Requested)  (Subscription Price)  (Amount Required)

[ ] B. Over-Subscription Privilege                                  .000 x $                   = $              (*)
                                                       ------------------  --------------------  -------------------
                                                       (Shares Requested)  (Subscription Price)  (Amount Required)

       Amount of Check Enclosed or Amount in Notice of Guaranteed Delivery (total of A + B)    = $
                                                                                                --------------------

       Make check payable to the order of "BioTime, Inc."

   
       (*) The over-subscription privilege can be exercised by certain shareholders only, as described in the
           Prospectus.
    

[ ] C. Sell any remaining unexercised Rights

[ ] D. Sell all of my Rights.

_______________________________________ Please provide your telephone number    Day (___)___________________________
Signature of Subscriber(s)/Seller(s)                                        Evening (___)___________________________

Social Security Number or Tax ID Number: _______________________________________________

SECTION II: TO TRANSFER RIGHTS: (except pursuant to C and D above)

For  value  received, __________________________ of the Rights represented by this Subscription Certificate are assigned to

- ----------------------------------------------------------       ----------------------------------------------------------
Social  Security  Number  or Tax ID Number of Assignee           (Print Full Name of Assignee

- ----------------------------------------------------------       ----------------------------------------------------------
Signature(s)  of Assignor(s)                                     (Print Full Address including postal Zip Code)

The  signature(s)  must  correspond  with the name(s) as written upon the face of this  Subscription  Certificate,  in every
particular, without alteration.

   
IMPORTANT:  For transfer, a signature guarantee must be provided by an eligible financial institution which is a participant
in a recognized signature guarantee program.
    

SIGNATURE GUARANTEED BY:

- ------------------------------------

PROCEEDS FROM THE SALE OF RIGHTS MAY BE SUBJECT TO  WITHHOLDING OF U.S.  TAXES UNLESS THE SELLER'S  CERTIFIED U.S.  TAXPAYER
IDENTIFICATION  NUMBER (OR CERTIFICATION  REGARDING FOREIGN STATUS) IS ON FILE WITH THE SUBSCRIPTION AGENT AND THE SELLER IS
NOT OTHERWISE SUBJECT TO U.S. BACKUP WITHHOLDING.


[ ]  CHECK HERE IF RIGHTS ARE BEING  EXERCISED  PURSUANT TO A NOTICE OF GUARANTEED  DELIVERY  DELIVERED TO THE  SUBSCRIPTION
     AGENT PRIOR TO THE DATE HEREOF AND COMPLETE THE FOLLOWING:

     NAME(S) OF REGISTERED OWNER(S):
     WINDOW TICKET NUMBER (IF ANY):
     DATE OF EXECUTION OF NOTICE OF GUARANTEED DELIVERY:
     NAME OF INSTITUTION WHICH GUARANTEED DELIVERY: