FORM 6-K ~~SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549~~

~~Report~~SECURITIES ofAND ~~Foreign Private Issuer~~ EXCHANGE COMMISSION

Washington, ~~Pursuant~~D.C. ~~to Rule 13a-16 or 15d-16 of the Securities Exchange Act of 1934~~ 20549

~~For~~Report ~~the~~of ~~month~~Foreign Private Issuer Pursuant to Rule 13a-16 or 15d-16 of the ~~September~~Securities ~~2004~~Exchange Act of 1934

For the month of October 2004

Commission File Number 000-30716

AUTONOMY CORPORATION PLC

Cambridge Business Park Cowley Road Cambridge CB4 0WZ United Kingdom Tel: 44 (0)1223 448 000 (Address of principal executive offices)

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 ý [X] Form 40-F o [ ]

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T ~~Rule~~ Rule 101(b)(1): ____

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ____

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 [ ~~o No ý~~ ] No [X]

If "Yes" is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): 82- _____.

On ~~each~~ ~~of 5 August 2004~~October 20, ~~9 August~~ 2004, 10Autonomy ~~August~~Corporation ~~2004,~~plc ~~11 August 2004, 12 August 2004, 13 August 2004, 16 August 2004 and 25 August 2004,~~ (the "Company") issued a press release ~~through~~ announcing the ~~London Stock Exchange~~Company's ~~Registered~~results ~~News~~for ~~Service in accordance with~~ the ~~Listing~~three ~~Rules~~and ofnine ~~the~~months ~~United~~ended September ~~Kingdom Listing Authority~~30, ~~announcing~~2004. ~~details~~A ofcopy ~~purchases by the Company~~ of ~~its own shares for cancellation. Copies of~~ the ~~releases~~press ~~are~~release is attached hereto as Exhibit 99.1 and incorporated herein by reference.

Exhibits 99.1 Releases issued on each of 5 August 2004, 9 August 2004, 10 August 2004, 11 August 2004, 12 August 2004, 13 August 2004, 16 August 2004 and 25 August 2004 announcing details of purchases by the Company of its own shares for cancellation.

99.1	Press Release issued on October 20, 2004, announcing results for the three and nine months ended September 30, 2004.

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.

AUTONOMY CORPORATION PLC
Date: September 6, 2004 By: /s/ ANDREW M. KANTER
Andrew M. Kanter
Chief Operating Officer

AUTONOMY CORPORATION PLC

Date: October 21, 2004	By: /s/ Andrew M. Kanter
	Andrew M. Kanter
	Chief Operating Officer

AUTONOMY CORPORATION PLC

INDEX TO EXHIBITS

Exhibit Number		Description
99.1		Releases issued on each of 5 August 2004, 9 August 2004, 10 August 2004, 11 August 2004, 12 August 2004, 13 August 2004, 16 August 2004 and 25 August 2004 announcing details of purchases by the Company of its own shares for cancellation.

Exhibit Number	Description

99.1	Press Release issued on October 20, 2004, announcing results for the three and nine months ended September 30, 2004.

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		AUTONOMY CORPORATION PLC
Date: September 6, 2004	By:	/s/ ANDREW M. KANTER
		Andrew M. Kanter
		Chief Operating Officer

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