FORM 6-K

                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                        Report of Foreign Private Issuer
                    Pursuant to Rule 13a - 16 or 15d - 16 of
                      the Securities Exchange Act of 1934

                          For the month of August, 2006

                               HSBC Holdings plc

                              42nd Floor, 8 Canada
                        Square, London E14 5HQ, England


(Indicate by check mark whether the registrant files or will file annual
reports under cover of 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- ..............)



NOTIFICATION OF MAJOR INTERESTS IN SHARES


Section 198 - Companies Act 1985



The Company was notified on 21 August 2006 that Lehman Brothers International
(Europe) had a notifiable interest as at 17 August 2006 in 376,532,847 ordinary
shares of US$0.50 each in HSBC Holdings plc, representing approximately 3.27% of
the ordinary shares in issue.

A copy of the letter of notification, is quoted below.


N S Black
Assistant Secretary
HSBC Holdings plc



Letter to HSBC Holdings plc dated 21 August 2006 from Tara O'Hagan, Compliance
Department - Europe, Lehman Brothers International (Europe)


"Dear Sir/Madam,


                      S198 Companies Act 1985 (the "Act")


We write to inform you, pursuant to s198 of the Act, that as at the close of
business on 17th August, 2006, Lehman Brothers International (Europe) had an
interest in 376,532,847 ordinary shares of HSBC Holdings Plc (the "Company").
This represents 3.27% of the outstanding share capital of the Company.


Yours faithfully

For & on behalf of Lehman Brothers

Tara O'Hagan
Compliance Department - Europe"



                                    SIGNATURE

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.

                               HSBC Holdings plc

                                                By:
                                                Name:  P A Stafford
                                                Title: Assistant Group Secretary
                                                Date:  22 August 2006