For our March 2014 issue, we cover recent patents involving new applications of clustering and matrix factorization, particularly non-negative matrix factorization (NMF). This has become a very popular topic for exploration in academia and industry in recent years. Below, we consider several new  inventions in which NMF has been applied to summarization, collaborative filtering, classification, and anomaly detection. Number: 8,661,042 Title: Collaborative filtering with hashing Inventors: M. Scholz, S. Rajaram and R. Lukose Issued: February 25, 2014 Assignee: Hewlett-Packard Development Company, L.P. (Houston, TX). Number: 8,612,169 Title: Method and system for detecting anomalies in a bipartite graph Inventors: C. -Y. Lin, H. Tong Issued:  December 17, 2013 Assignee: International Business Machines Corporation (Armonk, NY) Number: 8,577,884 Title: Automated analysis and summarization of comments in survey response data Inventors: S. Poteet, A. Kao, S. Luh Issued:  November 5, 2013 Assignee: The Boeing Company (Chicago, IL) Number: 8,566,360 Title: System and method for automatically generating systematic reviews of a scientific field Inventors: C. Chen Issued:  Drexel University (Philadelphia, PA) Assignee: October 22, 2013 Number: 8,515,879 Title: Supervised nonnegative matrix factorization Inventors: S. -I. Huh, M. Gupta, J. Xiao Issued:  August 20, 2013 Assignee: Seiko Epson Corporation (Tokyo, JP) Number: 8,510,257 Title: Collapsed gibbs sampler for sparse topic models and discrete matrix factorization Inventors: C. Archambeau, G. Bouchard Issued:  August 13, 2013 Assignee: Xerox Corporation (Norwalk, CT) Number: 8,499,022 Title: Combining multiple clusterings by soft correspondence Inventors: B. Lo and Z. Zhang Issued:  July 30, 2013 Assignee: The Research Foundation of State University of New York (Binghamton, NY) Number: 8,452,770 Title: Constrained nonnegative tensor factorization for clustering Inventors: W. Peng Issued:  May 28, 2013 Assignee: Xerox Corporation (Norwalk, CT) Number: 8,412,757 Title: Non-negative matrix factorization as a feature selection tool for maximum margin classifiers Inventors: M. Gupta and J. Xiao Issued:  April 2, 2013 Assignee: Seiko Epson Corporation (Tokyo, JP) Number: 8,463,786 Title: Extracting topically related keywords from related documents Inventors: U. Udupa and S. Vysyaraju Issued:  June 11, 2013 Assignee: Microsoft Corporation (Redmond, WA) If you have an interesting patent to share when we next feature patents related to matrix factorization and clustering, or if you are especially interested in a signal processing research field that you would want to be highlighted in this section, please send an email to Shantanu Rane (rane AT merl DOT com).