In one example a fluid level sensing device is described. The device includes a sensing die having a number of fluid level sensors disposed thereon and a number of control devices, each control device corresponding to one of the number of fluid level sensors. A control device includes a comparing device to determine a state of a corresponding fluid level sensor. A state of the fluid level sensor is selected from the group consisting of a fluid state and a no fluid state. Each control device also includes a non-volatile memory device corresponding to the comparing device to indicate whether the corresponding fluid level sensor is at the fluid state or the no fluid state. A control device also includes a locking device to receive a write command and to irreversibly set the non-volatile memory device to the no fluid state based on the write command.