Magnetar Capital Partners LP : - Form 8.3 - CME Group Inc.

FORM 8.3

****PLEASE NOTE: This disclosure replaces other disclosures made from the period of April 25, 2018 through May 15, 2018. See below for further details.****

PUBLIC OPENING POSITION DISCLOSURE/DEALING DISCLOSURE BY

A PERSON WITH INTERESTS IN RELEVANT SECURITIES REPRESENTING 1% OR MORE

Rule 8.3 of the Takeover Code (the “Code”)

1.         KEY INFORMATION

2.         POSITIONS OF THE PERSON MAKING THE DISCLOSURE

(a)        Interests and short positions in the relevant securities of the offeror or offeree to which the disclosure relates following the dealing (if any)

All interests and all short positions should be disclosed.

Details of any open derivative or option positions, or agreements to purchase or sell relevant securities, should be given on a Supplemental Form 8 (Open Positions).

(b)        Rights to subscribe for new securities (including directors’ and other executive options)

If there are positions or rights to subscribe to disclose in more than one class of relevant securities of the offeror or offeree named in 1(c), copy table 2(a) or (b) (as appropriate) for each additional class of relevant security.

3.         DEALINGS (IF ANY) BY THE PERSON MAKING THE DISCLOSURE

(a)        Purchases and sales

 (b)       Derivatives transactions (other than options)

 (c)       Options transactions in respect of existing securities

(i)         Writing, selling, purchasing or varying

(ii)        Exercising

(d)        Other dealings (including subscribing for new securities)

The currency of all prices and other monetary amounts should be stated.

Where there have been dealings in more than one class of relevant securities of the offeror or offeree named in 1(c), copy table 3(a), (b), (c) or (d) (as appropriate) for each additional class of relevant security dealt in.

4.         OTHER INFORMATION

(a)        Indemnity and other dealing arrangements

(b)        Agreements, arrangements or understandings relating to options or derivatives

(c)        Attachments

Public disclosures under Rule 8 of the Code must be made to a Regulatory Information Service and must also be emailed to the Takeover Panel atmonitoring@disclosure.org.uk.  The Panel’s Market Surveillance Unit is available for consultation in relation to the Code’s dealing disclosure requirements on +44 (0)20 7638 0129.

The Code can be viewed on the Panel’s website atwww.thetakeoverpanel.org.uk.

Please note, the below are amended trade disclosures for the period of April 25, 3018 through May 15, 2018 to correctly categorize swap vs cash positions.  No other details, such and price or quantity are impacted by this amended disclosure.

3.         DEALINGS (IF ANY) BY THE PERSON MAKING THE DISCLOSURE

(a)        Purchases and sales

(b)        Derivatives transactions (other than options)