Phu Nhuan Jewelry Joint Stock Company (PNJ), one of Vietnam’s leading jewellery firms, received a significant boost after police investigators found no evidence that the company participated in illegal diamond importation or distribution during a widening smuggling probe. The development provides a degree of reassurance to investors and customers who were unsettled by the allegations circulating since the investigation began.
According to Thanh Hoa provincial police, PNJ maintained full and proper import documentation for its diamond purchases. The authorities concluded that the company’s internal distribution processes were controlled and compliant with applicable regulations. These findings contrast with broader allegations in the ongoing inquiry, which suggest that more than 30,000 diamonds, with an estimated value exceeding 1.5 trillion Vietnamese dong (about $57 million), may have been smuggled into Vietnam over a two-year period.
News of the probe and the resulting uncertainty rippled across Vietnam’s gemstone and jewellery market. Worries about the authenticity, certification and legal provenance of diamonds prompted several retailers to pause sales temporarily, while some consumers sought refunds or opted to sell stones at large discounts. Those market disruptions highlighted how sensitive consumer confidence is to concerns about supply chain integrity and certification credibility in the diamond sector.
Following the police statement clearing PNJ of direct involvement, PNJ’s share price reacted strongly in Hanoi stock trading, rising to the daily cap of 7 percent and moving toward its highest close in roughly a month. Despite that recovery, the stock still trades notably below the level it held before details of the investigation became public in early July, reflecting lingering investor caution as the broader inquiry continues.
While PNJ as a company was not accused of wrongdoing, investigators have implicated two individuals linked to PNJ’s fully owned gem-certification arm, PNJ Laboratory Co. The former director of the laboratory, Dang Ngoc Thao, and a laboratory staff member, Tran Tien Nhu Nghi, are alleged to have collaborated with foreign nationals to bring diamonds into Vietnam from Hong Kong outside official channels, reportedly for personal financial gain.
Police allege that Thao purchased smuggled diamonds and attempted to conceal their origins by altering identifying features. Specifically, investigators claim he removed GIA laser inscriptions from some stones, re-engraved them with PNJ Laboratory identification numbers, and issued replacement certificates. According to the police account, those modified diamonds were subsequently sold, with proceeds benefiting the individuals involved rather than the company.
Crucially for PNJ’s retail operations, authorities indicated the diamonds alleged to be smuggled were not introduced into PNJ’s retail sales network. Instead, the police say the proceeds from these transactions went directly to the individuals accused. That distinction was central to the police finding that PNJ itself had complied with import and distribution regulations.
Nevertheless, the case has exposed weaknesses in Vietnam’s broader diamond certification and trading ecosystem. The controversy has intensified calls for stronger controls on gemstone origins, more rigorous certification processes, and clearer labelling standards. In response, officials plan a month-long inspection of the country’s gemstone and precious-metals markets to review provenance documentation, testing procedures and compliance with regulatory requirements.
For customers and investors, PNJ’s clearance alleviates some immediate concerns, but it does not bring the wider investigation to a close. Police have stated they will continue probing other individuals and businesses thought to be connected to the alleged smuggling network, and further developments are possible as inquiries proceed.
Looking ahead, the episode may prompt meaningful changes across Vietnam’s jewellery industry. Greater emphasis on traceability, routine independent certification, tighter internal controls at laboratories, and enhanced regulatory oversight could emerge as priorities to rebuild trust and ensure that diamonds sold in the domestic market have transparent, verifiable origins. Such measures would aim to protect consumers and strengthen the long-term credibility of Vietnam’s diamond and jewellery sector.