Protective ring for a horology movement and horology movement including said protective ring

A horology movement comprising:

• a bridge assembly;
• a cage formed by a plate onto which the bridge assembly is fixed, said plate forming a radial shoulder with respect to the bridge assembly by a lower face;
• an oscillating mass which is rotatable with respect to said cage and extending radially beyond the bridge assembly;
• and
• a ring made from a material having ferromagnetic properties and including a tubular body extending between a first and a second axial end,
• wherein said ring is configured to encircle the bridge assembly and to extend axially towards the oscillating mass, and being adapted to form, by the first axial end, a stop limiting the angular displacement, about a radial axis, of the oscillating mass,
• wherein said ring includes a plurality of fixing members extending from the second axial end, engaged in housings formed in the lower face to fix the ring with respect to said horology movement,
• wherein the plurality of fixing members extend along a portion of the second axial end,
• wherein the ring includes an axial kerf extending between the first and the second axial end of said ring, said axial kerf separating a first longitudinal end and a second longitudinal end of said ring, and
• wherein one of the plurality of fixing members is positioned immediately adjacent the axial kerf at the first longitudinal end of the ring, and one of the plurality of fixing members is positioned immediately adjacent the axial kerf at the second longitudinal end of the ring.