Change in the variable tick threshold
March 7, 2006
Page 4 of 4

Clean Copy of Rule Amendments

351A: Options on Standard and Poor's 500 Stock Price IndexTM Futures

351A01.C. Minimum Fluctuations

The price of an option shall be quoted in index points. Each .01 index point (1 basis point) shall represent $2.5.
The minimum fluctuation shall be .10 index points ($25.00, also known as one tick). Trades may also occur at a
price of .05 index points ($12.50, also known as one-half tick), whether or not such trades result in the liquidation
of positions for both parties to the trade. A trade with a price equal to or less than 5.00 index points may also
occur at a price in multiples of .05 index points, e.g. 15 index points ($37.50, also known as one and one-half.
ticks), and 1.95 index points ($487.50 also known as nineteen and one-half ticks).

355C: Options on S&P 500/ CITIGROUP Growth Index Futures

355C01.C. Minimum Fluctuations

The price of an option shall be quoted in index points. Each .01 index point (1 basis point) shall represent $2.5.
The minimum fluctuation shall be .10 index points ($25.00, also known as one tick). Trades may also occur at a
price of .05 index points ($12.50, also known as one-half tick), whether or not such trades result in the liquidation
of positions for both parties to the trade. A trade with a price equal to or less than 5.00 index points may also
occur at a price in multiples of .05 index points, e.g., .15 index points ($37.50, also known as one and one-half
ticks), and 1.95 index points ($487.50, also known as nineteen and one-half ticks).

356C: Options on S&P 500/ CITIGROUP Value Index Futures

356C01.C. Minimum Fluctuations

The price of an option shall be quoted in index points. Each .01 index point (1 basis point) shall represent $2.5.
The minimum fluctuation shall be .10 index points ($25.00, also known as one tick). Trades may also occur at a
price of .05 index points ($12.50, also known as one-half tick), whether or not such trades result in the liquidation
of positions for both parties to the trade. A trade with a price equal to or less than 5.00 index points may also
occur at a price in multiples of .05 index points, e.g., .15 index points $37.50, also known as one and one-half
ticks), and 1.95 index points ($487.50, also known as nineteen and one-half ticks).

358A: Options on E-mini Standard and Poor's 500 Stock Price Index Futures

358A01.C. Minimum Fluctuations

The price of an option shall be quoted in index points. Each .01 index point (1 basis point) shall represent $0.50.
The minimum fluctuation shall be .25 index points (also known as one tick). Trades may also occur at a price of
.05 index points $2.50, whether or not such trades result in the liquidation of positions for both parties to the
trade. A trade with a price equal to or less than 5.00 index points may also occur at a price in multiples of .05
index points, $2.50.


cme é@

Chicago Mercantile Exchange
20 South Wacker Drive 312/930.1000 tef
Chicago, IL 60606-7499 312/466.4410 fax

www.cme.com

March 7, 2006

Ms. Jean A. Webb

Office of the Secretariat

Commodity Futures Trading Commission
Three Lafayette Centre

1155 21st Street, NW

Washington, DC 20581 =

903]

RE: Section 5c(c)(1), Part 40.6 - Amendment to the variable tick threshold level
for the S&P 500, S&P 500 Growth, S&P 500 Value,
and the E-Mini S&P 500 options on futures contracts.
CME Submission# 06-19.

Dear Ms. Webb:

Chicago Mercantile Exchange Inc. (“CME” or “Exchange”) hereby notifies the Commission of
an amendment the variable tick threshold level for the S&P 500, S&P 500 Growth, S&P 500 Value, and
the E-Mini S&P 500 options on futures contracts.

The Exchange certifies that these amendments comply with the Act and rules thereunder.

In response to customer demand, the Exchange will amend the variable tick threshold level on
the aforementioned options on futures contracts from 3.00 index points to 5.00 index points. This change
will be implemented on Sunday, April 2"? for a trade date of April 3". Rule language follows below with
additions underlined and deletions bracketed and struck out.

If you require any additional information regarding this action, please do not hesitate to contact
Ms. Ariel Hantin, Senior Research Analyst, at 312-559-4951. Please reference our CME Submission
#06-19 on all future correspondence regarding this notification.



Change in the variable tick threshold
March 7, 2006
Page 2 of 4

Sincerely,

John W. Labuszewski, Director
Research & Product Development

ce: Mr. Thomas M. Leahy and Mr. Steven B. Benton
CFTC Division of Market Oversight, Product Review & Analysis Section


Change in the variable tick threshold
March 7, 2006
Page 3 of 4

Text of Rule Amendments
(Additions are underlined, deletions are bracketed and overstruck.)

351A: Options on Standard and Poor's 500 Stock Price IndexTM Futures

351A01.C, Minimum Fluctuations

The price of an option shall be quoted in index points. Each .01 index point (1 basis point) shall represent $2.5.
The minimum fluctuation shall be .10 index points ($25.00, also known as one tick). Trades may also occur at a
price of .05 index points ($12.50, also known as one-half tick), whether or not such trades result in the liquidation
of positions for both parties to the trade. A trade with a price equal to or less than 5 [3].00 index points may also
occur at a price in multiples of .05 index points, e.g. 15 index points ($37.50, also known as one and one-half
ticks), and 1.95 index points ($487.50 also known as nineteen and one-half ticks).

355C: Options on S&P 500/ CITIGROUP Growth Index Futures

355C01.C. Minimum Fluctuations

The price of an option shall be quoted in index points. Each .01 index point (1 basis point) shall represent $2.5.
The minimum fluctuation shall be .10 index points ($25.00, also known as one tick). Trades may also occur at a
price of .05 index points ($12.50, also known as one-half tick), whether or not such trades result in the liquidation
of positions for both parties to the trade. A trade with a price equal to or less than 5 [3].00 index points may also
occur at a price in multiples of .05 index points, e.g., .15 index points ($37.50, also known as one and one-half
ticks), and 1.95 index points ($487.50, also known as nineteen and one-half ticks).

356C: Options on S&P 500/ CITIGROUP Value Index Futures

356C01.C. Minimum Fluctuations

The price of an option shall be quoted in index points. Each .01 index point (1 basis point) shall represent $2.5.
The minimum fluctuation shall be .10 index points ($25.00, also known as one tick). Trades may also occur at a
price of .05 index points ($12.50, also known as one-half tick), whether or not such trades result in the liquidation
of positions for both parties to the trade. A trade with a price equal to or less than 5 [3].00 index points may also
occur at a price in multiples of .05 index points, e.g., .15 index points $37.50, also known as one and one-half
ticks), and 1.95 index points ($487.50, also known as nineteen and one-half ticks).

358A: Options on E-mini Standard and Poor's 500 Stock Price Index Futures

358A01.C. Minimum Fluctuations

The price of an option shall be quoted in index points. Each .01 index point (1 basis point) shall represent $0.50.
The minimum fluctuation shall be .25 index points (also known as one tick). Trades may also occur at a price of
.05 index points $2.50, whether or not such trades result in the liquidation of positions for both parties to the
trade. A trade with a price equal to or less than 5 [3].00 index points may also occur at a price in multiples of .05
index points, $2.50.