Rio Alto Mining Limited RIOAF

Sentry`s Holdings

[dmuy]

For the January 2012 period from Sedar:

SII previously filed a report under Part 4 of National Instrument 62-103 in respect of the Reporting Issuer, for the month ended October 31, 2011, for securityholdings of 21,659,700 common shares of the Reporting Issuer (the “Shares”) representing a securityholding percentage of 12.80%. The net increase in Shares since the last report is
4,148,700 and the net increase in the securityholding percentage of Shares is 2.28%. The increase in securityholding percentage is due to a combination of acquisitions by accounts and funds managed by SII (the “SII Funds”) and an increase in the number of issued and outstanding Shares.