Filed Pursuant to Rule 424(b)(3)
File No. 333-118519

PROSPECTUS SUPPLEMENT NO. 4
(To Prospectus Dated November 22, 2004)

$195,000,000

Digital River, Inc.

1.25% Convertible Senior Notes due January 1, 2024 and
4,425,486 Shares of Common Stock, Subject to Adjustments, Issuable Upon
Conversion of the Notes

        This prospectus supplement relates to the resale from time to time by the holders of our 1.25% Convertible Senior Notes due January 1, 2024 and the shares of common stock issuable upon conversion of the notes.

        You should read this prospectus supplement in conjunction with the prospectus dated November 22, 2004, and this prospectus supplement is qualified in its entirety by reference to the prospectus, except to the extent that the information in this prospectus supplement supersedes the information contained in the prospectus. The prospectus is to be delivered with this prospectus supplement. The terms of the notes and the common stock issuable upon conversion of the notes are set forth in the prospectus.

        Our common stock is quoted on The Nasdaq National Market under the symbol "DRIV." The last reported sale price of our common stock on March 3, 2005 was $29.40 per share.

        See "Risk Factors" beginning on page 4 of the prospectus to read about factors you should consider before buying the notes or our common stock.

        Neither the Securities and Exchange Commission, any state securities commission nor any other regulatory authority, has approved or disapproved the securities nor have any of the foregoing authorities passed upon or endorsed the merits of this offering or the accuracy or adequacy of this prospectus supplement or the prospectus or the documents incorporated by reference therein. Any representation to the contrary is a criminal offense.

The date of this prospectus supplement is March 4, 2005.

        The prospectus is hereby amended and supplemented to include in the table under the caption "Selling Securityholders" beginning on page 47 of the prospectus the information regarding the selling securityholders listed below. This information was furnished to us by the selling securityholders as of the date of this prospectus supplement.

Name
   Principal Amount
of Notes
Beneficially Owned
and Offered(1)
   Common Stock
Beneficially Owned(2)
   Common Stock
Offered(3)
   Principal Amount of
Notes Owned
After Completion
of Offering
   Common Stock
Owned After
Completion
of Offering
  
*Citadel Credit Trading Ltd.(7)   4,600,000   104,396   104,396   (7 ) (7 )

*Citadel Equity Fund Ltd.(7)
 
52,900,000
 
1,200,554
 
1,200,554
 
(7
)
(7
)

Clinton Multistrategy Master Fund, Ltd.(8)
 
7,695,000
 
174,636
 
174,636
 
0
 
0
 

Clinton Riverside Convertible Portfolio Limited(8)
 
1,640,000
 
37,219
 
37,219
 
0
 
0
 

Sphinx Convertible Arbitrage (Clinton) Segregated Portfolio(8)
 
3,805,000
 
86,353
 
86,353
 
0
 
0
 
*
Registered broker-dealer or affiliate of a registered broker-dealer.

(1)
Amounts indicated may be in excess of the total amount registered due to sales or transfers exempt from the registration requirements of the Securities Act since the date upon which the selling holders provided to us the information regarding their notes and common stock.

(2)
Unless otherwise noted, represents shares of common stock issuable upon conversion of notes.

(3)
Assumes conversion of all of a holder's notes at a conversion rate of 22.6948 shares per $1,000 principal amount of notes and cash payments in lieu of any fractional interest. This conversion rate, however, is subject to adjustment as described in the prospectus under "Description of the Notes—Conversion Rights—Adjustment of Conversion Price and Other Adjustments." As a result, the number of shares of common stock offered by each selling securityholder pursuant to this prospectus may increase or decrease in the future.

(7)
Citadel Limited Partnership ("Citadel") is the trading manager of Citadel Equity Fund Ltd. and Citadel Credit Trading Ltd. and consequently has investment discretion over securities held by these entities, but disclaims beneficial ownership of the shares held by them. Kenneth C. Griffin indirectly controls Citadel and therefore has ultimate investment discretion over, but disclaims beneficial ownership of, securities held by these entities.
(8)
Voting and investment control is exercised by Michael Vacca, Chief Operating Officer of Clinton Group, Inc.