The Anglo Dutch publisher's shares leapt from 584p on February 20 to 627.5p yesterday, before falling back slightly before close of trading.
Reed's shares were also influenced by its acquisition of ChoicePoint for a total cost of $4.1bn (£2.1bn) payable in cash, which includes an equity value of $3.5bn and the assumption of $0.6bn of net debt.
ChoicePoint is a US risk management company that provides data and analytics to the insurance sector. It had revenues totalling $982m (£491m) in 2007.
Reed plans to divest its Business Information division to reduce exposure to advertising markets allowing it to concentrate on higher-growth online businesses.
The company said that difficult credit markets make a quick sale unlikely and it therefore remained opened to a demerger or break-up of its magazine portfolio.
RBI pubishes more than 100 titles, including Estates Gazette, B&C, Design News, Community Care, Flight International, Airline Business, Personnel Today, Cater & Hotel Keeper, New Scientist, Kellysearch, Elsevier, FEM Business, Midem and World Travel Market.
In January RBI closed its Elsevier Healthcare unit, resulting in the loss of 32 jobs and the closure of Doctor and Hospital Doctor, Independent Practitioner, Hospital Doctor's ancillary journal and Update.
The other main title, Practice Nurse, transferred to sister company the Medicine Publishing Group, based in Elsevier’s Oxford office.
Earlier this month, Reed cut 16 jobs at its business titles, with senior jobs being lost on Computer Weekly among others.
The company has also planned a significant restructuring programme to become more cost efficient but it is unclear how many jobs will be affected.
The restructuring of the company follows Reed's sell off of its Harcourt Education business for £2.5bn last year.
Sir Crispin Davis, Reed Elsevier's chief executive officer, said the sale of Harcourt Education and Business Information divisions will give it a more consistent and cohesive business.
He said: "The move to a more cohesive portfolio provides us with the opportunity to accelerate progress in consolidating and streamlining our technology, operations and back office support.
"In doing so, Reed Elsevier becomes a more integrated company with significant savings in cost structure. The restructuring plan announced today has an attractive payback and will make a meaningful addition to margin and earnings growth."
The company announced group revenues from continuing operations rose 2% in 2007 to £4.58bn.