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My preference would be for B. This is because the company blog is well established and so will have a lot more traffic to it so your blogs there are going to get seen and read. By showing an excerpt you are avoiding duplication but still driving traffic to the new website blog. Showing an excerpt on the company blog will entice people who are interested enough to click through to the new blog who may not otherwise have seen the article. Option A is least favourable for me because the search engines will still have to crawl the blog article on the old website so is wasting crawl budget on that site. Also, the move you are making is permanent and that is what a 301 tells the search engines. Th canonical tag is letting the search engines know which is the preferred URL to index. You really want to move the blog articles and then build new fresh links and traffic to them on the new website.