Eight initial public offerings are scheduled to price and begin trading by the end of this week in what is likely to become the busiest week for U.S. IPOs since December 2007.

The IPOs, from a broad array of companies, are expected to raise $3.3 billion.

Below is a list of the IPOs in order of expected pricing date. All are expected to begin trading the day after they price. Dates and deal terms can change before an IPO prices.

SEPTEMBER 23:

COLONY FINANCIAL INC:

Estimated proceeds: $250 mln (12.5 mln shares, $20 each)

Lead managers: Bank of America Merrill Lynch, Goldman Sachs, Morgan Stanley and UBS Investment Bank

Ticker/Exchange: CLNY on the New York Stock Exchange

Company: newly organized real estate finance company that will acquire, originate and manage a portfolio of real estate-related debt instruments.

NOTE: Originally scheduled to price Sept.22, and on Sept. 23, it halved its planned offer.

APOLLO COMMERCIAL REAL ESTATE FINANCE:

Estimated proceeds: $200 million - 20 mln shares, $20 each

Lead managers: JP Morgan, Citi, Barclays Capital

Ticker/Exchange: ARI on NYSE

Company: the private-equity backed REIT will originate, invest in, acquire and manage senior performing commercial real estate mortgage loans and commercial mortgage-backed securities.

NOTE: Originally scheduled to price Sept.22, and on Sept. 23, it halved its planned offer.

ARTIO GLOBAL INVESTORS INC:

Estimated proceeds: $585 mln (23.4 mln shares, $24-$26)

Lead manager: Goldman Sachs

Ticker/Exchange: ART on NYSE

Company: U.S. asset management arm of Swiss Bank Julius Baer

A123 SYSTEMS INC:

Estimated proceeds: $276 million (25.7 mln shares, $10-$11.50)

Lead managers: Morgan Stanley, Goldman Sachs

Ticker/Exchange: AONE on Nasdaq

Company: Designs, develops, manufactures and sells advanced, rechargeable lithium-ion batteries and battery systems used by carmakers.

NOTE: On Tuesday, A123 increased the size of its estimated price range to $10-$11.50, from $8-$9.50.

VITACOST.COM INC : VITC.O

Estimated proceeds: $132 mln (11 mln shares, $11-$13)

Lead managers: Jefferies & Co and Oppenheimer & Co

Ticker/Exchange: VITC on Nasdaq

Company: online retailer and direct marketer of dietary supplements

SEPTEMBER 24

SHANDA GAMES LTD: GAME.Oi

Estimated proceeds: $960 mln (83.5 mln ADRs, $10.50-$12.50)

Lead managers: Goldman Sachs (Asia), JP Morgan

Ticker/Exchange: GAME on Nasdaq

Company: Gaming unit of Chinese media co Shanda Interactive Entertainment Ltd

NOTE: Shanda Games raised the size of the offering to 83.5 million from 63 million ADRs on Wednesday.

FOURSQUARE CAPITAL CORP:

Estimated proceeds:$500 mln (25 mln shares, $20)

Lead managers: Bank of America Merrill Lynch, Morgan Stanley

Ticker/Exchange: FSQR on NYSE

Company: A REIT created by asset manager AllianceBernstein in part to buy toxic assets under U.S. Treasury program

SELECT MEDICAL HOLDINGS CORP:SEM.N

Estimated proceeds: $400 mln (33.3 mln shares, $11-$13)

Lead managers: Goldman Sachs, Morgan Stanley, Bank of America Merrill Lynch, JP Morgan.

Ticker/Exchange: SEM on NYSE

Company: operator of specialty hospitals, outpatient rehabilitation clinics.

Source: U.S. Securities and Exchange Commission filings, underwriters

(Writing by Phil Wahba; editing by Andre Grenon)