SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 6-K REPORT OF FOREIGN PRIVATE ISSUER Pursuant to Rule 13a-16 or 15d-16 of the Securities Exchange Act of 1934 For the month of December, 2005 PRUDENTIAL PUBLIC LIMITED COMPANY (Translation of registrant's name into English) LAURENCE POUNTNEY HILL, LONDON, EC4R 0HH, ENGLAND (Address of principal executive offices) Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F. Form 20-F X Form 40-F Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934. Yes No X If "Yes" is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): 82- Enclosures: Rule 2.10 Announcement Prudential plc 14 December 2005 For Immediate Release Prudential plc ("Prudential") Rule 2.10 announcement - Update of Relevant Securities in Issue In accordance with Rule 2.10 of the City Code on Takeovers and Mergers, Prudential confirms that since its previous announcement under Rule 2.10 the number of ordinary shares of 5p in issue has increased to 2,386,771,543. The International Securities Identification Number for Prudential's ordinary shares is GB0007099541. Additional information: Prudential plc is not affiliated in any manner with Prudential Financial, Inc, a company whose principal place of business is in the United States of America. Contact name for Enquiries Sylvia Edwards 020 7548 3826 Company official responsible for making notification Susan Henderson, Deputy Group Secretary 020 7548 3805 SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized. Date 14 December, 2005 PRUDENTIAL PUBLIC LIMITED COMPANY By: /s/ Susan Henderson Deputy Group Secretary