Polish cable operator Multimedia [MULPO.UL] became the latest firm to call off an initial public offering (IPO) on Thursday because of weak investor demand, joining companies including UK clothing chain Fat Face and Dutch property vehicle Domus.

The cancelled listings are making investors more cautious and reining in price expectations for major listings such as British discount retailer B&M and bank TSB, which want to sell their shares before the European summer holidays in case a so-called "IPO window" slams shut.

That window opened last year as an improving European economic outlook and cheap money released by central banks since the financial crisis drove big gains in European stock markets.

Total IPO share issuance in the year to date is $25.3 billion from 85 deals, more than triple the same period of 2013, with nearly a third raised in London.

The pick-up in IPOs has accelerated in recent months as shares extended their gains. But the prospect of interest rates being raised from record lows and lingering concerns over Europe's economic recovery are clouding the outlook for equities and investors are becoming more selective on new listings.

"Generally we have found deals rather expensive with too little upside left for the buyer," said Nicholas Melhuish, head of global equities at French asset manager Amundi, which has bought into just one deal this year.

Of those companies that did find enough buyers, some, including insurer Saga (>> Saga Group Ltd), were forced to price their shares at the bottom end of market expectations. Others, such as online firms AO.com (>> AO World PLC) and Just Eat (>> Just Eat PLC), saw their value fall below their issue price after listing.

Charterhouse's investment Card Factory was another to suffer heavy losses after it listed, a performance that has checked private equity's enthusiasm for bringing investments to market and encouraged it to seek alternative exits.

Last week, Apax [APAX.UL] scrapped plans to list foreign exchange business Travelex and opted to sell it outright, while Bridgepoint pulled its planned listing of Fat Face.

"The market is heavily saturated and investors are experiencing fatigue with a lot of the issues that are coming to market," said Bertie Thomson, senior investment manager at Aberdeen Asset Management.

"The lofty valuations of the majority of stocks we've done due diligence work on meant it has been very hard to get excited on a risk-reward basis," said Thomson, whose sole IPO purchase this year was Isle of Man-based Manx Telecom (>> Manx Telecom PLC).

Card Factory's troubles have also led to concerns that fellow high street retailer B&M could face pricing pressure in its IPO.

B&M "is a good business," a banker said. "Does Card Factory hurt it? I would hope not. Will it get the same valuation as it would three months ago? Probably not."

STOCK SLOWDOWN

A retreat in the stock market value of some smaller and medium-sized companies, particularly in Britain, appears to have increased their allure at the expense of new listings.

"The attractions of existing (listed) companies are now greater than they were three months ago," said David Lis, head of UK equities at Aviva Investors, "which means if you want to get these IPOs away you're going to have to price them much more cheaply than might have been the case a few months ago."

The FTSE mid-cap index <.FTMC> is trading down 0.5 percent in 2014 against a 1.4 percent gain in the blue-chip FTSE 100 <.FTSE>. Since its February high, however, the mid-cap index has fallen 5.2 percent against a 0.1 percent fall for the FTSE 100.

That divergence is less marked among the leading continental exchanges, however, many of which began their recent rally from a lower base and are benefiting from a recovery in peripheral euro zone markets after several years of underperformance.

In contrast with the UK, Germany has seen just two IPOs this year. The latest, car parts maker Stabilus , rose 9 percent on its first day, while 3D printer SLM (>> SLM Solutions Group AG) is also trading above its issue price.

The German mid-cap MDAX <.MDAX> has suffered less than its UK counterpart, down 0.5 percent from its January high, while the blue-chip DAX <.GDAXI> is up 1.6 percent.

For Geir Lode, head of global equities at Hermes Fund Managers, the IPO market had become "a little bit like real estate", with brokers talking up the market and resulting in "a lot of companies ... rushing lower-quality merchandise to the market".

Aviva Investors' Lis said that, while there was nothing inherently wrong with many of the companies brought to market, they faced a fight for investor cash with listed companies, many of which are raising cash to fund growth.

"There isn't a bottomless supply of cash and there's too much supply (of IPOs) in too short a period," Lis said. "And at the same time there are fundraisings going on as well, so ... there are a lot of claws on cash."

(Editing by David Holmes and Tom Pfeiffer)

By Jemima Kelly, Freya Berry and Simon Jessop