Arm's IPO debut is coming today at a valuation of $54.5 billion

• Arm will become the biggest IPO in the US since 2021 when it makes its market debut on Thursday.
• The chip designer will be valued at $54.5 billion and raise about $4.9 billion, per Bloomberg.
• Arm's IPO could prompt more firms to list after a prolonged slump.

Arm, the chip designer owned by SoftBank, will become the biggest US IPO since 2021 when it makes its market debut on Thursday. 

The listing will raise about $4.9 billion and values the company at about $54.5 billion, according to Bloomberg calculations.