Rio Alto Mining Limited RIOAF

The buyer is Sentry

[DaveAu]

Posted yesterday on Sedar:

EARLY WARNING REPORT UNDER THE ALTERNATIVE

MONTHLY REPORTING SYSTEM OF

NATIONAL INSTRUMENT 62-103

1. Name and Address of the eligible institutional investor:

Sentry Investments Inc. (“SII”)

130 King Street West

Suite 2850

Toronto, Ontario, Canada

M5X 1A4

2. Name of Reporting Issuer:

Rio Alto Mining Limited (the “Reporting Issuer”).

3. Period for which the report is filed:

September 2011.

4. Net increase or decrease in the number or principal amount of securities, and in the

eligible institutional investor’s securityholding percentage in the class of securities,

since the last report filed by the eligible institutional investor under Part 4 of National

Instrument 62-103 or the early warning requirements:

SII has not previously filed a report under Part 4 of National Instrument 62-103 in respect

of the Reporting Issuer.

5. Designation and number or principal amount of securities and the eligible institutional

investor’s securityholding percentage in the class of securities at the end of the month

for which the report is made:

SII exercises control over 19,860,300 common shares of the Reporting Issuer (the

“Shares”). SII’s securityholding percentage represented by such Shares is 11.77%. The

Shares were acquired by accounts and funds managed by SII (the “SII Funds”). SII has

control over but not ownership of the Shares.

6. Designation and number or principal amount of securities and the percentage of

outstanding securities referred to under Section 5 over which:

a) the eligible institutional investor, either alone or together with any joint actors, has

ownership and control;

Not applicable.

b) the eligible institutional investor, either alone or together with any joint actors, has

ownership but control is held by other entities other than the eligible institutional

investor or any joint actor; and

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Not applicable.

c) the eligible institutional investor, either alone or together with any joint actors, has

exclusive or shared control but does not have ownership.

SII exercises control over 19,860,300 Shares of the Reporting Issuer. SII’s

securityholding percentage represented by such Shares is 11.77%. The Shares were

acquired by the SII Funds. SII has control over but not ownership of the Shares.

7. The purpose of the eligible institutional investor and any joint actors in acquiring or

disposing of ownership of, or control over, the securities, including any future

intention to acquire ownership of, or control over, additional securities of the reporting

issuer.

SII’s acquisitions were made in the ordinary course of business and were made for

investment purposes. Neither SII nor the SII Funds have made any determination with

respect to future ownership of, or control over, any additional securities of the Reporting

Issuer. SII and the SII Funds may in the future acquire additional securities of the

Reporting Issuer in the market or through private or other transactions, sell all or some

portion of the Shares of the Reporting Issuer they control or own, or enter into derivative

or other transactions with respect to their Shares of the Reporting Issuer.

8. The general nature and the material terms of any agreement, other than lending

arrangements, with respect to securities of the reporting issuer entered into by the

eligible institutional investor, or any joint actor, and issuer of the securities or any

other entity in connection with transaction or occurrence resulting in the change in

ownership or control giving rise to the report, including agreements with respect to the

acquisition, holding, disposition or voting of any of the securities.

Not applicable.

9. Name of any joint actors in connection with the disclosure required by Appendix G of

National Instrument 62-103.

Not applicable.

10. If applicable, a description of any change in any material fact set out in a previous

report by the eligible institution investor under the early warning requirements or Part

4 of National Instrument 62-103 in respect of the reporting issuer’s securities.

Not applicable.

11. Eligibility to file reports under the alternative monthly reporting system:

SII is eligible to file this report under the alternative monthly reporting system (Part 4) of

National Instrument 62-103.

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12. Declaration:

The filing of this report is not an admission that any entity named in this report owns or

controls any described securities or is a joint actor with another named entity.

DATED this 7th day of October, 2011.