The fund selector favourite told investors a note released on Monday that the €3.9 billion European equity fund will be closed to new investors from October 4 with only current investors able to increase their subscription.
However, the Citywire AA-rated manager and his team have set a limit on possible further subscriptions from the fund's existing shareholders to a maximum amount of €500,000 per day, per existing shareholder.
Since mid-2011 the fund has experienced a surge in inflows, with its assets doubling over the past two years from €1.9 billion in May 2011 to €3.9 billion at the end of August 2013, according to Lipper data.
Following the news, Citywire Global contacted the Walewski to find out more about the reasons behind his decision.
'Following the rapid growth of the ALKEN European Opportunities, as European equities return to favour, we have decided to temporarily soft close the product,' he said.'We have always favoured controlled and sustainable growth. Although there are no capacity constraints at this stage, we believe it is in the best interest of our existing investors to control the inflows into the ALKEN European Opportunities fund.
'The ALKEN Absolute Return and ALKEN Small Cap remain open to new subscriptions and the soft closure of the ALKEN European Opportunities Fund will be reassessed in the future subject to market conditions and investment resources at the firm.'
The European Opportunities fund was initially launched in January 2006. In less than two years it reached an asset size peak of €4.1 billion shortly before the financial crisis which led to considerable outflows.
This latest surge in investor assets is the closest the fund has come since that date of breaching the €4 billion mark.
Over the past five years, the fund has doubled the performance of the Stoxx Europe 600 TR of 24.3%, returning 50.9% over this period in euro terms.