IEC 62149-9:2014 covers the performance specification for seeded reflective semiconductor optical amplifier (RSOA) transceivers used for the fibre optic telecommunication and optical data transmission applications. The performance standard contains a definition of the product performance requirements together with a series of sets of tests and measurements with clearly defined conditions, severities, and pass/fail criteria. The tests are intended to be run on a "once-off" basis to prove any product's ability to satisfy the performance standard's requirements. A product that has been shown to meet all the requirements of a performance standard can be declared as complying with the performance standard, but should then be controlled by a quality assurance/quality conformance program. Key words: seeded reflective semiconductor optical amplifier (RSOA) transceivers