Acquire / Acquisition is a term used when any company take the financial & operational control of any company by purchasing 51% or more share of the concerned company.

in attaining financial control.

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financial control in a financial company or institution.

A company is taken over for operational or financial reasons. Here financially taken over is the most appropriate substitution for the term.

(1) In a partnership firm the working partner has the financial control over the business of the firm. He looks after all the payments and receipts. In case of dispute other partners change the working partner and another partner of the firm takes over the charge of finance.He achieves Financial Control over the firm.
(2) In a proprietary concern the proprietor sells the business and the party takes financial control over the business.
(3)The Managing Director having the financial control over the company is changed and a new Managing Director is appointed by Board of Directors in such a case also Financial Control is taken over/achieved by the new MD.
(4) Here we are speaking about financial control only but not over all control. Finance includes financial planning, receipts, payments etc. But that may not include technical control that may be looked after by MD (Technical)