Key Inclusion Criteria:

   1. Histologically confirmed DLBCL

   2. Chemotherapy-refractory disease, defined as one or more of the following:

      - Stable disease (duration of stable disease must be less than or equal to 6
      months) or progressive disease as best response to most recent chemotherapy
      containing regimen

      - Disease progression or recurrence less than or equal to 12 months of prior
      autologous stem cell transplantation (SCT)

   3. Individuals must have received adequate prior therapy including at a minimum:

      - anti-CD20 monoclonal antibody unless investigator determines that tumor is
      CD20-negative; and

      - an anthracycline containing chemotherapy regimen

   4. At least one measurable lesion per revised International Working Group (IWG) Response
   Criteria

   5. Age 18 years or older

   6. Eastern cooperative oncology group (ECOG) performance status of 0 or 1

   7. Adequate organ and bone marrow function

   8. All individuals or legally appointed representatives/caregivers, must personally sign
   and date the institutional review board (IRB)/independent ethics committee (IEC)
   approved consent form before initiating any study specific procedures or activities.

Key Exclusion Criteria:

   1. History of malignancy other than nonmelanoma skin cancer or carcinoma in situ (e.g.,
   cervix, bladder, breast) or follicular lymphoma unless disease free for at least 3
   years

   2. History of allogeneic stem cell transplantation

   3. Prior CAR therapy or other genetically modified T cell therapy

   4. Clinically significant active infection

   5. Known history of infection with HIV or hepatitis B (HBsAg positive) or hepatitis C
   virus (anti-HCV positive)

   6. Individuals with detectable cerebrospinal fluid malignant cells or brain metastases or
   with a history of cerebrospinal fluid malignant cells or brain metastases

   7. History of a seizure disorder, cerebrovascular ischemia/hemorrhage, dementia,
   cerebellar disease, or any autoimmune disease with central nervous system (CNS)
   involvement

   8. History of autoimmune disease. Participants with a history of autoimmune-related
   hypothyroidism on a stable dose of thyroid replacement hormone and participants with
   controlled type 1 diabetes mellitus on a stable insulin regimen may be eligible for
   this study.

   9. History of idiopathic pulmonary fibrosis, organizing pneumonia (e.g., bronchiolitis
   obliterans), drug-induced pneumonitis, idiopathic pneumonitis, or evidence of active
   pneumonitis per chest computed tomography (CT) scan at screening. History of radiation
   pneumonitis in the radiation field (fibrosis) is allowed.

10. Prior treatment with PD-L1 inhibitor, PD-1 inhibitor, anti-CTLA4, anti-CD137,
   anti-OX40 or other immune checkpoint blockade or activator therapy with the exception
   of Individuals who received atezolizumab in this study and are eligible for
   re-treatment

11. Prior CD19 targeted therapy

Note: Other protocol defined Inclusion/Exclusion criteria may apply