UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G
Under the Securities Exchange Act of 1934




(Name of Issuer)		Catalyst Biosciences, Inc.

(Title of Class of Securities)	Common Stock

(CUSIP Number)			14888D208
(Date of Event Which Requires Filing of this Statement)	April 14, 2017

Check the appropriate box to designate the rule pursuant to which this
Schedule
is filed:
      [   ]Rule 13d-1(b)
      [ X  ]Rule 13d-1(c)
      [   ]Rule 13d-1(d)

      CUSIP No. 		14888D208

          1.Names of Reporting Persons.

	     Laurence W.Lytton

2. Check the Appropriate Box if a Member of a Group (See Instructions)

a)..........................................................................

(b)..........................................................................

      3.SEC Use Only

      4.Citizenship or Place of Organization

      		USA

      5.Sole Voting Power 	220,500

      6.Shared Voting Power

      7.Sole Dispositive Power	220,500
      8.Shared Dispositive Power


      9.Aggregate Amount Beneficially Owned by Each Reporting
      Person			220,500


      10.Check if the Aggregate Amount in Row (9) Excludes Certain Shares
(See Instructions).................................


      11.Percent of Class Represented by Amount in Row (9)
      				8.1%


      12.Type of Reporting Person (See Instructions)

			IN

            Item 1.

      (a)Name of Issuer		Catalyst Biosciences, Inc.

      (b)Address of Issuer's Principal Executive Offices

			260 Littlefield Ave.
			South San Francisco, California




	      Item 2.

      (a)Name of Person Filing	Laurence W. Lytton

      (b)Address of Principal Business Office or, if none, Residence

		467 CPW
		N.Y., NY  10025

      (c)Citizenship			USA

      (d)Title of Class of Securities	Common

      (e)CUSIP Number			14888D208

      Item 3. 	not applicable


      Item 4.Ownership.

      (a)Amount beneficially owned: 220,500

      (b)Percent of class: 		8.1%

      (c)Number of shares as to which the person has:

      (i)Sole power to vote or to direct the vote 	220,500.

      (ii)Shared power to vote or to direct the vote

      (iii)Sole power to dispose or to direct the disposition of  220,500.

      (iv)Shared power to dispose or to direct the disposition of


      Item 5.Ownership of Five Percent or Less of a Class:
      	If this statement is being filed to report the fact that as of the
        date hereof the reporting person has ceased to be the beneficial
        owner of more than 5 percent of the class of securities, check the
 	following ( ).


      Item 6.Ownership of More than Five Percent on Behalf of Another Person.

			Not applicable

      Item 7.Identification and Classification of the Subsidiary Which
Acquired the Security Being Reported on By the Parent Holding Company

			Not applicable

      Item 8.Identification and Classification of Members of the Group

			Not applicable

      Item 9.Notice of Dissolution of Group

			Not applicable

      Item 10.Certification

      By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above were not acquired and are not held
for the purpose of or with the effect of changing or influencing the control
of the issuer of the securities and were not acquired and are not held
in connection with or as a participant in any transaction having that
purpose or effect.


SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete
and correct.
      ___4/13/17____________________________
      Date
      ____s/ Laurence W. Lytton____________________________
      Signature
      _____Laurence W. Lytton___________________________
      Name/Title