Conn. Agencies Regs. § 12-711(b)-4
Example 1: A plumber, who is a resident of Rhode Island, carries on his business from an office in Danielson, Connecticut. He has maintenance contracts with housing authorities in the Worcester, Massachusetts area which require him to regularly perform his services at various locations in and around Worcester. This individual is considered to be carrying on business in Connecticut (by reason of his office in this state) and in Massachusetts (because his business is conducted there with a fair measure of permanency and continuity).
Example 2: Assume the same facts as in Example 1, except that the taxpayer carries on his business from an office in Auburn, Massachusetts and has maintenance contracts with housing authorities in northeast Connecticut. This individual is considered to be carrying on business in Massachusetts (by reason of his office there) and in Connecticut (because his business is conducted in this state with a fair measure of permanency and continuity).
Example 1: The president of a large Texas corporation flies to New Haven to meet a prospective supplier, spends two days there meeting with the supplier and then flies back to Texas. The president had never been to Connecticut on business, nor is she scheduled to return. Her visit is secondary to her primary out-of-state employment duties. She is not considered to be rendering personal services as an employee in Connecticut, and her presence for employment purposes is casual, isolated and inconsequential.
Example 2: A nonresident professional ice hockey player plays in all eighty games for his team in 1992 over parts of two seasons. Four of the games are played in Hartford. He is considered to be rendering personal services as an employee in Connecticut and his presence is not ancillary to his primary employment duties. Thus, his presence for employment purposes is not casual, isolated and inconsequential.
Example 3: A dentist employed by a health maintenance organization in Portland, Maine comes to Connecticut for a paid six-week training course in pediatric dentistry. Her presence for business in Connecticut is ancillary to her primary employment duties elsewhere and is therefore casual, isolated and inconsequential. She is not considered to be rendering personal services as an employee in Connecticut.
Example 4: A New York attorney operating as a sole practitioner in New York City is retained by a Connecticut business in connection with a pending lawsuit in a Connecticut court. All of the trial preparation occurs in New York but the attorney appears in court in Connecticut. He earns more than $6,000 in Connecticut by his activity under § 12-711(c)-4 of this Part. This nonresident is considered to be carrying on business in Connecticut because the part of the fee apportioned to Connecticut is more than $6,000 and the duties performed in Connecticut are not ancillary to his primary duties.
Example 5: The facts are the same as in the previous example, except the attorney earns $1,000 from his activity in Connecticut. The attorney is not considered to be carrying on business in Connecticut because he does not earn more than $6,000 directly from his activity in Connecticut, and therefore his presence for business in Connecticut is casual, isolated and inconsequential.
Example 6: The facts are the same as in Example 5, except that the attorney derived more than $5,000 in income from Connecticut real estate that he rented to others. His presence would not be considered casual, isolated and inconsequential because the sum of his rental income from Connecticut sources plus his income from the practice of law in Connecticut exceeds $6,000.
Example 7: The regional manager of a New England shoe manufacturer has an office in the company's headquarters in Providence, Rhode Island. The company maintains three retail outlet stores in Connecticut, and the manager spends one week each month assisting in the management of each of the three Connecticut retail stores. The manager is not performing duties which are ancillary to her primary employment duties, so her presence for business in Connecticut is not casual, isolated and inconsequential, and she is considered to be rendering personal services as an employee in Connecticut.
Example 8: The West Coast sales manager of a large Connecticut corporation is based in San Francisco, California and performs all of his duties as sales manager from the San Francisco office. The sales manager flies to Hartford at least once a year for a two-week sales symposium and as needed for technical training sessions. This is the only contact the manager has with Connecticut. Because the services are merely ancillary to his primary employment carried on in California, this nonresident's presence for business in Connecticut is casual, isolated and inconsequential. He is not considered to be rendering personal services as an employee in Connecticut.
Example 9: A nonresident computer systems development engineer is employed in the Illinois office of a Connecticut- based corporation. She is sent to the Connecticut headquarters from January to June 1992 to become familiar with the development and operation of the company's latest computer. The engineer receives her regular salary during the six months in Connecticut. She is considered to be rendering personal services as an employee in Connecticut because her presence for training in Connecticut is not ancillary to her primary employment duties.
Example: A nonresident individual was employed until late 1991 at a place of business in Connecticut and then is transferred by her employer to its place of business in New Hampshire. She and her employer had previously agreed that the compensation for her services rendered during 1991 was not to be paid to her until 1992. The compensation paid for her 1991 services constitutes income derived from or connected with Connecticut sources for her 1992 taxable year, even though she was not performing personal services within Connecticut during 1992.
Conn. Agencies Regs. § 12-711(b)-4