Software transactional memory (STM) has evolved as an alternative for traditional lock-based process synchronization. It promises greater degree of concurrency and faster execution. This paper proposes a simple, lightweight, and yet efficient implementation of OFTM. The major contribution of the paper is in proposing a new STM algorithm that uses simple data structure. This does not require any contention manager toward ensuring progress condition, atomicity, and serializability of transactions besides maintaining data consistency. Experimental simulation on random data set establishes the merit of the proposed solution. © Springer India 2015.