Disciplined LargeCap Blend Fund (Prospectus Summary): | Disciplined LargeCap Blend Fund

DISCIPLINED LARGE CAP BLEND FUND    

Supplement dated June 16, 2011

to the Class A, Class B, and Class C Prospectus

for Principal Funds, Inc.

dated March 1, 2011

(as supplemented on March 14, 2011 and March 15, 2011)  

This supplement updates information currently in the Prospectus. Retain this supplement with the  

Prospectus.  

On June 14, 2011, the Board of Directors of Principal Funds, Inc. approved the acquisition of the assets  

of the Disciplined LargeCap Blend Fund by the Principal Capital Appreciation Fund. This proposal will be  

submitted for shareholder vote at a Special Meeting of Shareholders of Disciplined LargeCap Blend Fund  

tentatively scheduled for October 3, 2011. Additional information about this proposal will be provided in  

the Proxy Statement/Prospectus that is expected to be mailed to record date shareholders of Disciplined  

LargeCap Blend Fund in August 2011. If shareholders approve this proposal, the acquisition is expected  

to occur on or about October 14, 2011.