Open source license does not mean giving up intellectual property rights. You can only license the work if you own the rights to the work. MIT License starts

Open source license does not mean giving up intellectual property rights. You can only license the work if you own the rights to the work. MIT License starts with copyright notice: Copyright (c) <year> <copyright holders> Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal ....