Antibody-Drug Conjugates (ADCs) are a rapidly growing class of oncology therapeutics wherein a potent cytotoxic drug is conjugated to the antibody molecule. The impact of drug conjugation on the antibody's conformation needs to be evaluated. Additionally, the drug conjugation can also affect various physical properties of the antibody molecule which in turn can affect its stability and aggregation propensity. This presentation summarizes results from our study on aggregation of a lysine-conjugated ADC and its unconjugated mAb under accelerated heat and agitation stresses. Additionally, we also highlight spectroscopic and DSC based analytical approaches that can be used to detect subtle differences between the ADC and mAb.