The LHCb collaboration achieved important results in the exotic spectroscopy sector using $pp$ collision data collected with the LHCb detector at centre-of-mass energies of $\sqrt{s} = 7$ and $\sqrt{s} =8$ TeV during Run1, corresponding to an integrated luminosity of 3 $fb^{-1}$. These results include the discovery of two pentaquark candidates by an amplitude analysis of $\Lambda^0_b \to J/\psi pK^-$ decays, by a model-independent approach and by an amplitude analysis of $\Lambda^0_b \to J/\psi p \pi^-$ decays. Following the interest arised from these discoveries, further LHCb studies related to the pentaquark spectroscopy have been carried out, including the first observation of $\Lambda^0_b \to \chi_{c(1,2)} p K^-$ decays, a search for weakly decaying $b$-flavoured pentaquarks, and a search for exotic states in $\Lambda^0_b \to \Lambda^+_c p \bar{p} \pi^-$ decays.