Regulators grounded the 737 MAX worldwide following a second fatal crash in March that killed all 157 people on board an Ethiopian Airlines plane, and is fighting to get the jet back in service later this year.

It said on Tuesday that an unidentified business jet customer had ordered one 737 MAX jet, with monthly data suggesting it was converted to the MAX from another variant.

Boeing also reported four apparent order conversions in favor of the MAX in April but a major tentative deal for 200 of the jets from British Airways owner IAG, announced at the Paris Airshow in June, has yet to show up as a firm order.

Boeing's net order tally, including cancellations, was a negative 84 for the first nine months of 2019, also hit by the bankruptcy of India's Jet Airways, which resulted in Boeing removing 210 aircraft from its order backlog.

European rival Airbus in contrast has 127 net orders this year and is within reach of its full-year goal of 880-890 deliveries despite factory snags.

Boeing deliveries fell 47% to 302 aircraft in the first nine months of 2019. Deliveries totaled 26 aircraft in September, down from 87 a year earlier.

Prior to the MAX grounding, Boeing, which delivered 806 aircraft in 2018, was targeting 900 aircraft deliveries this year.

(This story corrects paragraphs 1, 3, 4 to show that the latest order had been preceded by 4 similar orders in April)

(Reporting by Ankit Ajmera in Bengaluru; Editing by Shailesh Kuber)