We report the results of a globally coordinated photometric campaign to search for transits by the P \sim 30 { d } and P \sim 60 { d } outer planets of the 3-planet system orbiting the nearby M-dwarf Gl 876 .
These two planets experience strong mutual perturbations , which necessitate use of a dynamical ( four-body ) model to compute transit ephemerides for the system .
Our photometric data have been collected from published archival sources , as well as from our photometric campaigns that were targeted to specific transit predictions .
Our analysis indicates that transits by planet “ c ” ( P \sim 30 { d } ) do not currently occur , in concordance with the best-fit i = 50 ^ { \circ } co-planar configuration obtained by dynamical fits to the most recent radial velocity data for the system .
Transits by planet “ b ” ( P \sim 60 { d } ) are not entirely ruled out by our observations , but our data indicate that it is very unlikely that they occur .
Our experience with the Gl 876 system suggests that a distributed ground-based network of small telescopes can be used to search for transits of very low mass M-stars by terrestrial-sized planets .