Established on July 31st, 1987, Prag Bosimi Synthetics (PBSL) was founded through a partnership between Assam Industrial Development Corporation (AIDC) and Bombay Silk Mills (BOSIMI). The company primarily focuses on the production of Polyester Yarn. In February 1992, PBSL launched a public issue worth Rs 27.1 crore to partially fund the manufacturing of 15,000 tons per annum (tpa) of polyester filament yarn (PFY), setting up downstream facilities for draw texturising and draw twisting of yarn, and to cater to its working capital needs. The overall project cost was estimated at Rs 188 crore. PBSL produces various types of polyester yarn, including 30 denier, 50 denier, 75 denier, twisted, and dyed assortments. The company has a technical collaboration with EMS Inventa, Switzerland, for the production of POY/PFY. Its textile division commenced commercial operations in 1993. However, the final phase of the project, which involved installing 6 direct spinning lines and was expected to be completed by August 1995, faced delays due to factors such as adverse law and order conditions, inadequate infrastructure, and a shortage of skilled manpower. The project is anticipated to be finalized this year, with financial institutions extending additional short-term finance in the form of redeemable convertible preference shares worth Rs 30.96 crore. In the fiscal year 1999-2000, the company incurred a net loss of Rs. 983.13 lakhs, prompting the State Bank of India to approve a rehabilitation and restructuring proposal, along with covering 40% of the company's working capital requirements. In 2010, PBSL established a wholly-owned subsidiary for implementing the Textile Park Project, completed refurbishment work, restored a 132 KVA dedicated High Tension Power supply by ASEB on-site with the necessary transformers, and installed a new UPS System to ensure uninterrupted power supply. Another texturising machine was installed in 2013, and in the fiscal year 2015-16, the company introduced a separate division named Bosimi Apparel under the Brand Name 'BOSIMI'. In 2017-18, new machinery worth Rs 22 crore was inaugurated and commissioned, leading to the commencement of commercial production and the sale of products in West Bengal and Assam.