The Takeover Code has a concept called ‘acting in concert’. Persons acting in concert form a ‘concert party’.

The technical definition (from the Takeover Panel’s website) is given below, but basically it means people or businesses that are acting together to control a company or block a takeover attempt.

Acting in concert

This definition has particular relevance to mandatory offers and further guidance with regard to behaviour which constitutes acting in concert is given in the Notes on Rule 9.1.

Persons acting in concert comprise persons who, pursuant to an agreement or understanding (whether formal or informal), co-operate to obtain or consolidate control (as defined below) of a company or to frustrate the successful outcome of an offer for a company. A person and each of its affiliated persons will be deemed to be acting in concert all with each other (see Note 2 below).

Without prejudice to the general application of this definition, the following persons will be presumed to be persons acting in concert with other persons in the same category unless the contrary is established:

1. a company (“X”) and any company which controls#, is controlled by or is under the same control as X, all with each other;
2. a company (“Y”) and any other company (“Z”) where one of the companies is interested, directly or indirectly, in 30% or more of the equity share capital in the other, together with any company which would be presumed to be acting in concert with either Y or Z under presumption (1), all with each other;
3. a company’s pension schemes, and the pension schemes of any company with which the company is presumed to be acting in concert under presumption (1) or (2), with the company;
4. the directors of a company (together with their close relatives and the related trusts of any of them) with the company;
5. an investment manager of or investment adviser to:
   1. an offeror;an investor in a new company (or other vehicle) formed for the purpose of making an offer; orthe offeree company,
   with the offeror or offeree company (as appropriate), together with any person controlling#, controlled by or under the same control as that investment manager or investment adviser;
6. a connected adviser with its client and, if its client is acting in concert with an offeror or the offeree company, with that offeror or offeree company respectively, in each case in respect of the interests in shares of that adviser and persons controlling#, controlled by or under the same control as that adviser (except in the capacity of an exempt fund manager or an exempt principal trader);
7. the directors of a company which is subject to an offer or a possible offer (together with their close relatives and the related trusts of any of them) from the beginning of the relevant period as defined in Rule 21.1(b) or, where Note 9 on Rule 21.1 applies, from the beginning of the offer period. (See also Note 5);
8. a person, the person’s close relatives, and the related trusts of any of them, all with each other;
9. the close relatives of a founder of a company to which the Code applies, their close relatives, and the related trusts of any of them, all with each other; and
10. shareholders in a private company or members of a partnership who sell their shares or interests in consideration for the issue of new shares in a company to which the Code applies, or who, in connection with an initial public offering or otherwise, become shareholders in a company to which the Code applies.

For the purposes of presumptions (1) and/or (2):

1. a reference to a company includes any other undertaking (including a partnership or a trust) or any legal or natural person;
2. under presumption (1), interests of either 30% or more in a company’s shares carrying voting rights or the majority of a company’s equity share capital do not dilute through a chain of ownership;
3. under presumption (2), interests of 30% or more in a company’s equity share capital dilute through a chain of ownership;
4. the reference in presumption (2) to a company being “indirectly” interested in the equity share capital in another company refers only to the economic rights attached to such shares and not to any voting rights carried by such shares; and
5. except for the purposes of establishing whether a person is acting in concert with a new company (or other vehicle) formed for the purpose of making an offer (see paragraph (a) of Note 7 below), if an investor invests in a fund or company and that fund or company in turn invests in another fund or company, the investor’s indirect interests in the latter fund or company will (in addition to the investor’s direct interests) only be taken into account in determining whether the investor and that fund or company are presumed to be acting in concert under presumption (2) if each link in the chain of interests represents 30% or more of the relevant fund’s limited partnership interests or the relevant company’s equity share capital.