An application was submitted by Pioneer Overseas Corporation to request the authorization of the genetically modified maize stack 1507 x 59122 x MON 810 x NK603, resistant against certain lepidopteran pests, protected against corn rootworm larvae, and glufosinate-ammonium and glyphosate tolerant, and all sub-combinations of the individual events as present in the segregating progeny, for food and feed uses, and import and processing, in accordance with articles 5 and 17 of Regulation (EC) N? 1829/2003 GM Food and GM Feed. The unique identifier assigned to 1507 x 59122 x MON 810 x NK603 maize is DAS-?15?7-1xDAS-59122-7xMON-??81?-6xMON-??6?3-6. The genetically modified maize line 1507 x 59122 x MON 810 x NK603 has been obtained by conventional crossing of four genetically modified single maize events: 1507, 59122, MON 810 and NK603 without any new genetic modification. The EU-RL GMFF has previously validated, and declared fit for purpose, the detection methods for the single events 1507, 59122, MON 810 and NK603 (see: http://gmo-crl.jrc.ec.europa.eu/statusofdoss.htm). In line with the approach defined by the ENGL (http://gmo-crl.jrc.ec.europa.eu/doc/Min_Perf_Requirements_Analytical_methods.pdf) the EU-RL GMFF therefore has carried out only an in-house verification of the performance of each validated method when applied to DNA extracted from 1507 x 59122 x MON 810 x NK603. The herewith reported in-house verification study lead to the conclusion that the individual methods meet the ENGL performance criteria also when applied to DNA extracted from the GM maize stack 1507 x 59122 x MON 810 x NK603.