In frequency division duplex transceivers, a part of the own transmit signal leaks into the receiver due to the limited stop-band isolation from the transmit to the receive port of the duplexer. In addition, analog front-end components have a ?nite second-order input intercept point (IIP2). In direct conversion architectures, these two facts result in an intermodulation distortion (IMD2) self-interference. One major problem is that this IMD2 interference always falls directly into the baseband of the receiver regardless of the operating transmit and receive frequency, desensitizing the receiver during normal operation. This contribution presents an adaptive ?ltering algorithm to cancel the transmitter induced IMD2 self-interference based on a nonlinear least-mean-squares approach. The algorithm can deal with highly frequency-selective duplexer stop-bands, requires only a low computational complexity and thus outperforms existing solutions like adaptive Volterra kernel based algorithms.