SEOUL, Aug 4 (Reuters) - South Korean retail shareholder platform ACT said on Tuesday it had launched a campaign to call an extraordinary ‌shareholders' meeting at Samsung Electronics, urging the chipmaker to buy back about $32 ‌billion worth of shares and set limits on performance bonuses. The move comes after Samsung shares lost over ‌one third of their value ⁠since hitting record-highs in June, despite the artificial intelligence boom. The falls were driven by a sharp wave of deleveraging ⁠and renewed skepticism regarding the durability of AI infrastructure spending. The proposed meeting could consider a proposal to approve a 45.5 trillion won ($31.79 billion) share buyback programme, it said. A ‌second proposal would seek to require shareholder ​approval for an upper limit on performance bonuses ​tied to company operating profit.