Cell surface receptor that binds to glycosaminoglycans, including chondroitin sulfate proteoglycans and heparan sulfate proteoglycans (PubMed:11865065, PubMed:17178832). Binding to chondroitin sulfate and heparan sulfate proteoglycans has opposite effects on PTPRS oligomerization and regulation of neurite outgrowth (By similarity). Contributes to the inhibition of neurite and axonal outgrowth by chondroitin sulfate proteoglycans, also after nerve transection (PubMed:17967490). Plays a role in stimulating neurite outgrowth in response to the heparan sulfate proteoglycan GPC2. Required for normal brain development, especially for normal development of the pituitary gland and the olfactory bulb. Functions as tyrosine phosphatase (PubMed:17967490). Mediates dephosphorylation of NTRK1, NTRK2 and NTRK3 (PubMed:17967490). Plays a role in down-regulation of signaling cascades that lead to the activation of Akt and MAP kinases. Down-regulates TLR9-mediated activation of NF-kappa-B, as well as production of TNF, interferon alpha and interferon beta (By similarity). H2O + O-phospho-L-tyrosyl-[protein] = L-tyrosyl-[protein] + phosphate Homodimer (PubMed:17178832). Binding to large heparan sulfate proteoglycan structures promotes oligomerization. Binding to chondroitin sulfate proteoglycan does not lead to oligomerization (By similarity). Interacts (via Ig-like domains) with NTRK1 and NTRK3, but does not form detectable complexes with NTRK2 (PubMed:17967490, PubMed:25385546). Interacts (via extracellular domain) with the heparan sulfate proteoglycans AGRN and COL18A1 (PubMed:11865065). Detected along neurites and at axon growth cones. Detected in embryonic brain, dorsal root ganglion and spinal cord (PubMed:7600997). Detected in embryonic retina (at protein level) (PubMed:11865065). Detected in embryonic brain, spinal cord, dorsal root ganglion, trigeminal ganglion, ganglia associated with the precardinal vein and vagus nerve, the inner and outer nuclear layer of the retina, limb, breast muscle, heart, gut and lung. A cleavage occurs, separating the extracellular domain from the transmembrane segment. This process called 'ectodomain shedding' is thought to be involved in receptor desensitization, signal transduction and/or membrane localization (By similarity). Belongs to the protein-tyrosine phosphatase family. Receptor class 2A subfamily.