Deal needs time to pass muster with regulators

XM and Sirius have agreed not to call off their planned merger until at least May 1, giving the thorny deal more time to pass muster with regulators.

Execs at both satellite radio companies have expressed confidence that the deal will be completed, but monopoly concerns on the part of the Justice Dept. and FCC have held up approval for more than a year.

The $4 billion stock swap theoretically becomes less of a monopoly concern as technology continues to evolve. Car audio systems, for example, increasingly feature digital technology that goes well beyond radio signals.

Financials have improved over the past year for both companies, though both stocks have been flat over the period as regulators take their time assessing the deal.

Last month, XM said it was financially capable of remaining a standalone company should the merger not gain approval.

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