Halfway through June and with no US IPOs on the immediate radar, it is looking likely investors will see no deals at all this month - the first June without an offering in more than 40 years.

Data provider Dealogic said its researchers looked back as far as 1970 and couldn't find any year with no initial public offerings in June. The month is normally an active month for IPOs in the US, as bankers work to complete deals before the July 4 holiday.