Fiat Chrysler had a credit balance of 13.8 million credits at the end of the 2014 model year.
This is the first time Toyota has chosen to sell credits.
Daimler AG's Mercedes-Benz unit has acquired about 1.4 million credits, including 500,000 additional credits from Nissan, according to the report. Without the credits, it would be in a deficit since it had about 200,000 credits remaining at the end of 2014.
Ferrari NV, which was spun off by Fiat Chrysler earlier this year, acquired another 175,000 credits and has purchased 265,000 credits.
Tesla sold all of its 2013 and 2014 greenhouse gas emissions credits to Fiat Chrysler. Tesla earned $216.3 million in all regulatory credit sales in 2014 and $194.4 million in 2013 but does not breakout transactions.