Editing CAC 40 (section)

===Selection===
The CAC 40 index composition is reviewed quarterly by an independent Index Steering Committee ({{langx|fr|Conseil Scientifique}}).<ref name="profile" /> If any changes are made, they are
effected a minimum of two weeks after the review meeting.<ref name="profile" /> At each review date, the companies listed on Euronext Paris are ranked according to [[Float (finance)|free float]] [[Market capitalization|market capitalisation]] and [[stock|share]] turnover over the prior 12 months.<ref name="rules">{{cite web
 |url          = http://www.euronext.com/fic/000/050/871/508718.pdf
 |title        = Rules for the CAC 40 Index
 |publisher    = Euronext
 |date         = January 2009
 |access-date   = 2009-12-17
 |archive-url  = https://web.archive.org/web/20110616051936/http://www.euronext.com/fic/000/050/871/508718.pdf#
 |archive-date = 16 June 2011
 |url-status     = dead
}}</ref> From the top 100 companies in this ranking, forty are chosen to enter the CAC 40 such that it is "a relevant benchmark for [[Investment management|portfolio management]]" and "a suitable underlying asset for [[Derivative (finance)|derivatives]] products".<ref name="rules" /> If a company has more than one class of shares traded on the exchange, only the most actively traded of these will be accepted into the index (generally this will be the ordinary share).<ref name="rules" />