Boltsy - ASX300 simply represents the top 300 listed companies...

Boltsy - ASX300 simply represents the top 300 listed companies on ASX ranked by market cap. ASX200 and ASX100 are the top 200 and 100 respectively. Fund managers often make this part of the criteria for looking at a company to be part of their portfolios for a number of reasons - retail fund investors feel more secure if they see a fund investing in names they know, and these stocks are usually highly liquid and easily traded. Often too fund managers simply have too much money to spend on taking a position in a stock. They can't buy into smaller companies - the volume isn't there for it to be practical and they'd end up owning too much of the company.