** Shares in Rubis RUBF.PA are up around 5% after a shareholder grouping that includes French businessmen Patrick Molis bought more shares in the French petroleum products distributor
** Rubis said in a regulatory filing that as of April 8 Concert Molis holds 9.37% of the ordinary shares of the company, while Compagnie nationale de navigation standalone holds 9.06% of the ordinary shares
** The stake increase could revive speculation in the shares, Portzamparc says, even if the company's SCA status seems difficult to challenge
** It could also trigger proposed resolutions from Molis or even a potential challenge to the appointments of CFO Marc Jacquot and CEO of Rubis Energie, Portzamparc adds
** The stock is at the top of France's SBF120 .SBF120
(Reporting by Anna Peverieri)
((Anna.peverieri@thomsonreuters.com))